1. Reciprocating pumps are no more to be seen in industrial applications (in comparison to centrifugal pumps) because of
A. high initial and maintenance cost
B. lower discharge
C. lower speed of operation
D. necessity of air vessel
E. all of the above. Answer: A
2. In a centrifugal pump casing, the flow of water leaving the impeller, is
A. rectilinear flow
B. radial flow
C. free vortex motion
D. forced vortex
E. none of the above. Answer: C
3. Head developed by a centrifugal pump depends on
A. impeller diameter
B. speed
C. fluid density
D. type of casing
E. A. and B. above. Answer: E
4. For starting an axial flow pump, its delivery valve should be
A. closed
B. open
C. depends on starting condition and flow desired
D. could be either open or closed
E. partly open and partly closed. Answer: B
5. The efficiency of a centrifugal pump is maximum when its blades are
A. straight
B. bent forward
C. bent backward
D. bent forward first and then backward
E. bent backward first and then forward. Answer: C
6. In a centrifugal pump casing, the flow of water leaving the
A. radial
B. radial
C. centrifugal
D. rectilinear
E. vortex. Answer: E
7. Centrifugal pump is started with its delivery valve
A. kept fully closed
B. kept fully open
C. irrespective of any position
D. kept 50% open
E. none of the above. Answer: A
8. Axial flow pump is started with its delivery valve
A. kept fully closed
B. kept fully open
C. irrespective of any position
D. kept 50% open
E. none of the above. Answer: B
9. When a piping system is made up primarily of vertical lift and very little pipe friction, the pump characteristics should be
A. horizontal
B. nearly horizontal
C. steep
D. first rise and then fall
E. none of the above. Answer: C
10. One horsepower is equal to
A. 102 watts
B. 75 watts
C. 550 watts
D. 735 watts
E. 33000 watts. Answer: D
HYDRAULIC MACHINES Mcqs
11. Multistage centrifugal pumps are used to obtain
A. high discharge
B. high head
C. pumping of viscous fluids
D. high head and high discharge
E. high efficiency. Answer: B
12. When a piping system is made up primarily of friction head and very little of vertical lift, then pump characteristics should be
A. horizontal
B. nearly horizontal
C. steep
D. first rise and then fall
E. none of the above. Answer: B
13. In a single casing, multistage pump running at constant speed, the capacity rating is to be slightly lowered. It can be done by
A. designing new impeller
B. trimming the impeller size to the required size by machining
C. not possible
D. some other alterations in the impeller
E. none of the above. Answer: B
14. If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge
A. same quantity of liquid
B. 0.75 Q
C. Q/0.75
D. 1.5 Q
E. none of the above. Answer: A
15. The horse power required in above case will be
A. same
B. 0.75 B.H.P.
C. B.H.P./0.75
D. 1.5 B.H.P.
E. none of the above. Answer: B
16. Low specific speed of a pump implies it is
A. centrifugal pump
B. mixed flow pump
C. axial flow pump
D. any one of the above
E. none of the above. Answer: A
17. The optimum value of vane exit angle for a centrifugal pump impeller is
A. 10-15°
B. 20-25°
C. 30-40°
D. 50-60°
E. 80-90°. Answer: B
18. In a centrifugal pump, the liquid enters the pump
A. at the top
B. at the bottom
C. at the center
D. from sides
E. none of the above. Answer: C
19. For small discharge at high pressure, following pump is preferred
A. centrifugal
B. axial flow
C. mixed flow
D. propeller
E. reciprocating. Answer: E
20. In centrifugal pumps, maximum efficiency is obtained when the blades are
A. straight
B. bent forward
C. bent backward
D. radial
E. given aerofoil section. Answer: C
21. Motion of a liquid in a volute casing of a centrifugal pump is an example of
A. rotational flow
B. radial
C. forced spiral vortex flow
D. forced cylindrical vortex flow
E. spiral vortex flow. Answer: E
22. For very high discharge at low pressure such as for flood control and irrigation applications, following type of pump is preferred
A. centrifugal
B. axial flow
C. reciprocating
D. mixed flow
E. none of the above. Answer: B
23. Medium specific speed of a pump implies it is
A. centrifugal pump
B. mixed flow pump
C. axial flow pump
D. any one of the above
E. none of the above. Answer: B
24. High specific speed of a pump implies it is
A. centrifugal pump
B. mixed flow pump
C. axial flow pump
D. any one of the above
E. none of the above. Answer: C
25. Indicator diagram of a reciprocating pump is a graph between
A. flow vs swept volume
B. pressure in cylinder vs swept volume
C. flow vs speed
D. pressure vs speed
E. swept volume vs speed. Answer: B
26. Low specific speed of turbine implies it is
A. propeller turbine
B. Francis turbine
C. impulse turbine
D. any one of the above
E. none of the above. Answer: C
27. Any change in load is adjusted by adjusting following parameter on turbine
A. net head
B. absolute velocity
C. blade velocity
D. flow
E. relative velocity of flow at inlet. Answer: D
28. Runaway speed of a hydraulic turbine is
A. full load speed
B. the speed at which turbine runner will be damaged
C. the speed if the turbine runner is allowed to revolve freely without load and with the wicket gates wide open
D. the speed corresponding to maximum overload permissible
E. none of the above. Answer: C
29. The maximum number of jets generally employed in impulse turbine without jet interference is
A. 4
B. 6
C. 8
D. 12
E. 16. Answer: B
30. Medium specific speea of turbine implies it is
A. propeller turbine
B. Francis turbine
C. impulse turbine
D. any one of the above
E. none of the above. Answer: B
Hydraulic Machines Multiple Choice Questions and Answers pdf :-
31. High specific speed of turbine implies it is
A. propeller turbine
B. Francis turbine
C. impulse turbine
D. any one of the above
E. none of the above. Answer: A
32. The specific speed of turbine is defined as the speed of a unit
A. of such a size that it delivers unit dis-charge at unit head
B. of such a size that it delivers unit dis-charge at unit power
C. of such a size that it requires unit power per unit head
D. of such a size that it produces unit horse power with unit head
E. none of the above. Answer: D
33. Puck up the wrong statement about centrifugal pump
A. discharge a diameter
B. head a speed2
C. head a diameter
D. Power a speed3
E. none of the above is wrong. Answer: A
34. A turbine pump is basically a centrifugal pump equipped additionally with
A. adjustable blades
B. backward curved blades
C. vaned diffusion casing
D. inlet guide blades
E. totally submerged operation facility. Answer: C
35. Casting of a centrifugal pump is designed so as to minimize
A. friction loss
B. cavitation
C. static head
D. loss of kinetic energy
E. starting time. Answer: D
36. In reaction turbine, draft tube is used
A. to transport water downstream without eddies
B. to convert the kinetic energy to flow energy by a gradual expansion of the flow cross-section
C. for safety of turbine
D. to increase flow rate
E. none of the above. Answer: B
37. Guide angle as per the aerofoil theory of Kaplan turbine blade design is defined as the angle between
A. lift and resultant force
B. drag and resultant force
C. lift and tangential force
D. lift and drag
E. resultant force and tangential force. Answer: A
38. Francis turbine is best suited for
A. medium head application from 24 to 180 m
B. low head installation up to 30 m
C. high head installation above 180 m
D. all types of heads
E. none of the above. Answer: A
39. The flow rate in gear pump
A. increases with increase in pressure
B. decreases with increase in pressure
C. more or less remains constant with in-crease in pressure
D. unpredictable
E. none of the above. Answer: C
40. Impulse turbine is generally fitted
A. at the level of tail race
B. little above the tail race
C. slightly below the tail race
D. about 2.5 m above the tail race to avoid cavitation
E. about 2.5 m below the tail race to avoid cavitation. Answer: B
41. Francis, Kaplan and propeller turbines fall under the category of
A. Impulse turbines
B. Reaction turbines
C. Axial flow turbines
D. Mixed flow turbines
E. Reaction-cum-impulse turbines. Answer: B
42. Reaction turbines are used for
A. low head
B. high head
C. high head and low discharge
D. high head and high discharge
E. low head and high discharge. Answer: E
43. The discharge through a reaction turbine with increase in unit speed
A. increases
B. decreases
C. remains unaffected
D. first increases and then decreases
E. first decreases and then increases. Answer: B
44. The angle of taper on draft tube is
A. greater than 15°
B. greater than 8°
C. greater than 5°
D. less than 8°
E. less than 3°. Answer: D
45. Specific speed for reaction turbines ranges from
A. 0 to 4.5
B. 10 to 100
C. 80 to 200
D. 250 to 300
E. none of the above. Answer: B
46. In axial flow fans and turbines, fluid enters and leaves as follows
A. radially, axially
B. axially, radially
C. axially, axially
D. radially, radially
E. combination of axial and radial. Answer: C
47. Which place in hydraulic turbine is most susceptible for cavitation
A. inlet of draft rube
B. blade inlet
C. guide blade
D. penstock
E. draft tube exit. Answer: A
48. Air vessels in reciprocating pump are used to
A. smoothen flow
B. reduce acceleration to minimum
C. increase pump efficiency
D. save pump from cavitation
E. increase pump head. Answer: B
49. Saving of work done and power by fitting an air vessel to single acting reciprocating pump is of the order of
A. 39.2%
B. 49.2%
C. 68.8%
D. 84.8%
E. 91.6%. Answer: D
50. Saving of work done and power by fitting an air vessel to double acting reciprocating pump is of the order of
A. 39.2%
B. 49.2%
C. 68.8%
D. 84.8%
E. 91.6%. Answer: A
51. According to fan laws, for fans having constant wheel diameter, the air or gas capacity varies
A. directly as fan speed
B. square of fan speed
C. cube of fan speed
D. square root of fan speed
E. none of the above. Answer: A
52. According to fan laws, for fans having constant wheel diameter, the pressure varies
A. directly as fan speed
B. square of fan speed
C. cube of fan speed
D. square root of fan speed
E. none of the above. Answer: B
53. According to fan laws, for the fans having constant wheel diameters, the power demand varies
A. directly as fan speed
B. square of fan speed
C. cube of fan speed
D. square root of fan speed
E. none of the above. Answer: C
54. According to fan laws, at constant speed and capacity, the pressure and power vary
A. directly as the air or gas density
B. inversely as square root of density
C. inversely as density
D. as square of density
E. as square root of density. Answer: A
55. According to fan laws, at constant pressure, the speed capacity and power vary
A. directly as the air or gas density
B. inversely as square root of density
C. inversely as density
D. as square of density
E. as square root of density. Answer: B
56. According to fan laws, at constant weight of air or gas, the speed, capacity and pressure vary
A. directly as the air or gas density
B. inversely as square root of density
C. inversely as density
D. as square of density
E. as square root of density. Answer: C
57. Pressure intensifier increases the pressure in proportion to
A. ratio of diameters
B. square of ratio of diameters
C. inverse ratio of diameters
D. square of inverse ratio of diameters
E. fourth power of ratio of diameters. Answer: B
58. A hydraulic accumulator normally consists of
A. two cylinders, two rams and a storage device
B. a cylinder and a ram
C. two co-axial rams and two cylinders
D. a cylinder, a piston, storage tank and control valve
E. special type of pump with storage device and a pressure regulator. Answer: B
59. A hydraulic intensifier normally consists of
A. two cylinders, two rams and a storage device
B. a cylinder and a ram
C. two co-axial rams and two cylinders
D. a cylinder, a piston, storage tank and control valve
E. special type of pump with storage device and a pressure regulator. Answer: C
60. Hydraulic accumulator is used for
A. accumulating oil
B. supplying large quantities of oil for very short duration
C. generally high pressures to operate hydraulic machines
D. supplying energy when main supply fails
E. accumulating hydraulic energy. Answer: D
61. Maximum impulse will be developed in hydraulic ram when
A. waste valve closes suddenly
B. supply pipe is long
C. supply pipe is short
D. ram chamber is large
E. supply pipe has critical diameter, Answer: A
Comparative cost theory does not tell what the actual terms of trade will be. It gives only the upper and lower limits of the range in which the trade between the two countries will be mutually beneficial.
The terms of trade refer to the rate of exchange and are determined by the cost ratios of production. If Indian wheat is exchanged for English cloth at a rate of 1 Wheat = .9 Cloth, then all gains of trade will go to India.
This is the upper limit. If Indian wheat is exchanged for English cloth at the rate of 1 Wheat = .5 Cloth, then all gains will go to England. This is the lower limit.
The actual terms of trade will be determined between these two limits. If Indian wheat is exchanged for English cloth at the rate of I Wheat = .7 Cloth, then the gains from trade will be evenly distributed between India and England.
The terms of trade as reflected by the cost ratios of production are represented through the offer curve. Line I represents the offer curve of India which is drawn on the basis of India’s barter rate (or cost ratio) 1 Wheat = .5 cloth.
Line E is the offer curve of England which is drawn on the basis of England’s domestic barter rate (or cost ratio) 1 Wheat = .9 Cloth. India’s offer curve (I line) shows that India wants more than .5 units of cloth for 1 unit of wheat exported.
England’s offer curve (E line) shows that England is willing to offer less than .9 units of cloth for 1 unit wheat imported. Thus, 1 Wheat = .5 Cloth and 1 Wheat = .9 Cloth are the two limits of the range in which the actual rate of exchange (terms of trade) will be determined.
The actual rate of exchange will be determined on the basis of the relative bargaining strength of the two countries. If the actual rate of exchange is fixed at the upper limit, i.e., 1 Wheat = .9 Cloth (as indicated by the offer curve E), it means India is powerful and England is weak in bargaining.
Or, in other words, England’s demand for India’s wheat is inelastic. In such a situation, the whole gain from trade (i.e., AB or .9 – 5 = .4 cloth per unit of wheat) will go to India.
On the other hand, if the actual rate of exchange is fixed at the lower limit, i.e., 1 Wheat = .5 Cloth (as indicated by the offer curve I), it means England is strong and India is weak in bargaining and the whole gain from trade (i.e., AB or .4 cloth per unit of wheat) will be received by England.
But, if both the countries are equally strong in bargaining the actual rate of exchange will be determined in the middle of the two limits, i.e., 1 Wheat = .7 Cloth (as indicated by the offer curve T).
The total gain from trade (i.e., AB or, .4 units of cloth per unit of wheat) will be equally distributed between India and England. India’s gain will be AC or .2 units of cloth per unit of wheat and England’s gain will be BC or .2 units of cloth per unit of wheat.
1. A body of mass ‘m’ moving with a constant velocity ‘v’ strikes another body of same mass moving with same velocity but in opposite direction. The common velocity of both the bodies after collision is
A.v
B.2v
C.4v
D.8v
Answer: B
2. The bellow figure shows the three coplanar forces P, Q and R acting at a point O. If these forces are in equilibrium, then
A.P/sin β = Q/sin α = R/sin ɣ
B.P/sin α = Q/sin β = R/sin ɣ
C.P/sin ɣ = Q/sin α = R/sin β
D.P/sin α = Q/sin ɣ = R/sin β
Answer: B
3. The centre of percussion of the homogeneous rod of length ‘L’ suspended at the top will be
A.L/2
B.L/3
C.3L/4
D.2L/3
Answer: D
4. The angle of inclination of the plane at which the body begins to move down the plane, is called
A.Angle of friction
B.Angle of repose
C.Angle of projection
D.None of these
Answer: A
5. Pick up wrong statement about friction force for dry surfaces. Friction force is
A.Proportional to normal load between the surfaces
B.Dependent on the materials of contact surface
C.Proportional to velocity of sliding
D.Independent of the area of contact surfaces
Answer: C
6. The term ‘Centroid’ is
A.The same as centre of gravity
B.The point of suspension
C.The point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis
D.None of the above
Answer: A
7. The C.G. of a plane lamina will not be at its geometrical centre in the case of a
A.Right angled triangle
B.Equilateral triangle
C.Square
D.Circle
Answer: A
8. If the masses of both the bodies, as shown in the below figure, are reduced to 50 percent, then tension in the string will be
A.Same
B.Half
C.Double
D.None of these
Answer: B
9. The moment of inertia of a thin rod of mass ‘m’ and length ‘l’, about an axis through its centre of gravity and perpendicular to its length is
A.ml2/4
B.ml2/ 6
C.ml2/8
D.ml2/12
Answer: D
10. Forces are called coplanar when all of them acting on body lie in
A.One point
B.One plane
C.Different planes
D.Perpendicular planes
Answer: B
11. A rubber ball is dropped from a height of 2 m. If there is no loss of velocity after rebounding, the ball will rise to a height of
A.1 m
B.2 m
C.3 m
D.4 m
Answer: B
12. A weight of 1000 N can be lifted by an effort of 80 N. If the velocity ratio is 20, the machine is
A.Reversible
B.Non-reversible
C.Ideal
D.None of these
Answer: A
13. Centre of gravity of a solid cone lies on the axis at the height
A.One fourth of the total height above base
B.One third of the total height above base
C.One-half of the total height above base
D.Three eighth of the total height above the base
Answer: A
14. The periodic time (T) is given by (where, ω = Angular velocity of particle in rad/s.)
A.ω/2π
B.2π/ω
C.2π × ω
D.π/ω
Answer: B
15. The resultant of two forces P and Q (such that P > Q) acting along the same straight line, but in opposite direction, is given by
A.P + Q
B.P – Q
C.P / Q
D.Q / P
Answer: B
16. When two elastic bodies collide with each other,
A.The two bodies will momentarily come to rest after collision
B.The two bodies tend to compress and deform at the surface of contact
C.The two bodies begin to regain their original shape
D.All of the above
Answer: D
17. The coefficient of friction depends upon
A.Nature of surfaces
B.Area of contact
C.Shape of the surfaces
D.All of the above
Answer: A
18. The angular velocity (in rad/s) of a body rotating at N revolutions per minute is
A.πN/60
B.πN/180
C.2πN/60
D.2πN/180
Answer: C
19. A block of mass m1, placed on an inclined smooth plane is connected by a light string passing over a smooth pulley to mass m2, which moves vertically downwards as shown in the below figure. The tension in the string is
A.m1/m2
B.m1. g. sin α
C.m1.m2/m1 + m2
D.m1. m2.g (1 + sin α)/(m1 + m2)
Answer: D
20. In determining stresses in frames by methods of sections, the frame is divided into two parts by an imaginary section drawn in such a way as not to cut more than
A.Two members with unknown forces of the frame
B.Three members with unknown forces of the frame
C.Four members with unknown forces of the frame
D.Three members with known forces of the frame
Answer: B
21. A machine having an efficiency greater than 50%, is known as
A.Reversible machine
B.Non-reversible machine
C.Neither reversible nor non-reversible machine
D.Ideal machine
Answer: A
22. The algebraic sum of moments of the forces forming couple about any point in their plane is
A.Equal to the moment of the couple
B.Constant
C.Both of above are correct
D.Both of above are wrong
Answer: A
23. In the lever of third order, load ‘W’, effort ‘P’ and fulcrum ‘F’ are oriented as follows
A.W between P and F
B.F between W and P
C.P between W and F
D.W, P and F all on one side
Answer: A
24. Which of the following statement is correct?
A.The algebraic sum of the forces, constituting the couple is zero
B.The algebraic sum of the forces, constituting the couple, about any point is the same
C.A couple cannot be balanced by a single force but can be balanced only by a couple of opposite sense
D.All of the above
Answer: D
25. A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if
A.The floor is smooth, the wall is rough
B.The floor is rough, the wall is smooth
C.The floor and wall both are smooth surfaces
D.The floor and wall both are rough surfaces
Answer: C
26. The skidding away of the vehicle on a level circular path can be avoided if the force of friction between the wheels and the ground is __________ the centrifugal force.
A.Less than
B.Greater than
C.Equal to
D.None of these
Answer: B
27. Coulomb friction is the friction between
A.Bodies having relative motion
B.Two dry surfaces
C.Two lubricated surfaces
D.Solids and liquids
Answer: A
28. The time of flight (t) of a projectile on an upward inclined plane is(where u = Velocity of projection, α = Angle of projection, and β = Inclination of the plane with the horizontal.)
A.t = g cos β/2u sin (α – β)
B.t = 2u sin (α – β)/g cos β
C.t = g cos β/2u sin (α + β)
D.t = 2u sin (α + β)/g cos β
Answer: B
29. Which of the following is the example of lever of first order?
A.Arm of man
B.Pair of scissors
C.Pair of clinical tongs
D.All of the above
Answer: D
30. Three forces acting on a rigid body are represented in magnitude, direction and line of action by the three sides of a triangle taken in order. The forces are equivalent to a couple whose moment is equal to
A.Area of the triangle
B.Twice the area of the triangle
C.Half the area of the triangle
D.None of these
Answer: B
31. The Cartesian equation of trajectory is (where u = Velocity of projection, α = Angle of projection, and x, y = Co-ordinates of any point on the trajectory after t seconds.)
A.y = (gx²/2u² cos²α) + x. tanα
B.y = (gx²/2u² cos²α) – x. tanα
C.y = x. tanα – (gx²/2u² cos²α)
D.y = x. tanα + (gx²/2u² cos²α)
Answer: C
32. The units of moment of inertia of an area are
A.kg-m²
B.m⁴
C.kg/m²
D.m³
Answer: B
33. The slope on the road surface generally provided on the curves is known as
A.Angle of friction
B.Angle of repose
C.Angle of banking
D.None of these
Answer: C
34. A force acting on a body may
A.Change its motion
B.Balance the other forces acting on it
C.Retard its motion
D.All of the above
Answer: D
35. The centre of gravity of an isosceles triangle with base (p) and sides (q) from its base is
A.[√(4p² – q²)]/6
B.(4p² – q²)/6
C.(p² – q²)/4
D.(p² + q²)/4
Answer: A
36. On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be
A.Towards the wall at its upper end
B.Away from the wall at its upper end
C.Upwards at its upper end
D.Downwards at its upper end
Answer: C
37. The velocity of a body on reaching the ground from a height h, is
A.2.√(gh)
B.√(gh)
C.√(2gh)
D.2g.√h
Answer: C
38. A framed structure, as shown in the below figure, is a
A.Perfect frame
B.Deficient frame
C.Redundant frame
D.None of the above
Answer: A
39. Lami’s theorem states that
A.Three forces acting at a point will be in equilibrium
B.Three forces acting at a point can be represented by a triangle, each side being proportional to force
C.If three forces acting upon a particle are represented in magnitude and direction by the sides of a triangle, taken in order, they will be in equilibrium
D.If three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two
Answer: D
40. The ratio of static friction to dynamic friction is always
A.Equal to one
B.Less than one
C.Greater than one
D.None of these
Answer: C
41. Which is the correct statement about law of polygon of forces?
A.If any number of forces acting at a point can be represented by the sides of a polygon taken in order, then the forces are in equilibrium
B.If any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon, then the forces are in equilibrium
C.If a polygon representing forces acting at a point is closed then forces are in equilibrium
D.If any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon taken in order, then the forces are in equilibrium
Answer: D
42. Moment of inertia of a triangular section of baseB.and height (h) about an axis through its base, is
A.bh3/4
B.bh3/8
C.bh3/12
D.bh3/36
Answer: C
43. Coefficient of friction is the
A.Angle between normal reaction and the resultant of normal reaction and the limiting friction
B.Ratio of limiting friction and normal reaction
C.The friction force acting when the body is just about to move
D.The friction force acting when the body is in motion
Answer: B
44. The forces, which meet at one point and their lines of action also lie on the same plane, are known as
A.Coplanar concurrent forces
B.Coplanar non-concurrent forces
C.Non-coplanar concurrent forces
D.Non-coplanar non-concurrent forces
Answer: A
45. A flywheel on a motor goes from rest to 1000 rpm in 6 sec. The number of revolutions made is nearly equal to
A.25
B.50
C.100
D.250
Answer: B
46. A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act
A.Towards the wall at its upper end
B.Away from the wall at its upper end
C.Downward at its upper end
D.Upward at its upper end
Answer: D
47. Pick up the incorrect statement from the following:
A.The C.G. of a circle is at its centre
B.The C.G. of a triangle is at the intersection of its medians
C.The C.G. of a rectangle is at the intersection of its diagonals
D.The C.G. of a semicircle is at a distance of r/2 from the centre
Answer: D
48. The range of projectile (R) on an upward inclined plane is
A.g. cos² β/2u². sin (α + β). cos α
B.2u². sin (α + β). cos α/g. cos² β
C.g. cos² β/2u². sin (α – β). cos α
D.2u². sin (α – β). cos α/g. cos² β
Answer: D
49. If three forces acting in one plane upon a rigid body, keep it in equilibrium, then they must either
A.Meet in a point
B.Be all parallel
C.At least two of them must meet
D.All the above are correct
Answer: D
50. In order to double the period of simple pendulum, the length of the string should be
A.Halved
B.Doubled
C.Quadrupled
D.None of these
Answer: C
51. The angle which an inclined plane makes with the horizontal when a body placed on it is about to move down is known as angle of
A.Friction
B.Limiting friction
C.Repose
D.Kinematic friction
Answer: C
52. The energy possessed by a body, for doing work by virtue of its position, is called
A.Potential energy
B.Kinetic energy
C.Electrical energy
D.Chemical energy
Answer: A
53. The centre of gravity of a uniform lamina lies at
A.The centre of heavy portion
B.The bottom surface
C.The midpoint of its axis
D.All of the above
Answer: C
54. The three forces of 100 N, 200 N and 300 N have their lines of action parallel to each other but act in the opposite directions. These forces are known as
A.Coplanar concurrent forces
B.Coplanar non-concurrent forces
C.Like parallel forces
D.Unlike parallel forces
Answer: D
55. Angle of friction is the
A.Angle between normal reaction and the resultant of normal reaction and the limiting friction
B.Ratio of limiting friction and normal reaction
C.The ratio of minimum friction force to the friction force acting when the body is just about to move
D.The ratio of minimum friction force to friction force acting when the body is in motion
Answer: A
56. Moment of inertia of a hollow circular section, as shown in the below figure about an axis perpendicular to the section, is ________ than that about X-X axis.
A.Two times
B.Same
C.Half
D.None of these
Answer: A
57. The frequency of oscillation of a compound pendulum is (where kG = Radius of gyration about the centroidal axis, and h = Distance between the point of suspension and C.G. of the body.)
A.2π. √(gh/kG² + h²)
B.2π. √(kG² + h²/gh)
C.1/2π. √(gh/kG² + h²)
D.1/2π. √(kG² + h²/gh)
Answer: C
58. The necessary condition for forces to be in equilibrium is that these should be
A.Coplanar
B.Meet at one point
C.BothA.andB.above
D.All be equal
Answer: C
59. Two forces are acting at an angle of 120°. The bigger force is 40 N and the resultant is perpendicular to the smaller one. The smaller force is
A.20 N
B.40 N
C.120 N
D.None of these
Answer: A
60. In actual machines
A.Mechanical advantage is greater than velocity ratio
B.Mechanical advantage is equal to velocity ratio
C.Mechanical advantage is less than velocity ratio
D.Mechanical advantage is unity
Answer: C
61. Coefficient of friction depends upon
A.Area of contact only
B.Nature of surface only
C.BothA.and (B)
D.None of these
Answer: B
62. Moment of inertia of a hollow rectangular section as shown in the below figure about X-X axis, is
A.(BD³/12) – (bd³/12)
B.(DB³/12) – (db³/12)
C.(BD³/36) – (bd³/36)
D.(DB³/36) – (db³/36)
Answer: A
63. Which of the following is a vector quantity?
A.Energy
B.Mass
C.Momentum
D.Angle
Answer: C
64. The maximum velocity of a particle moving with simple harmonic motion is
A.ω
B.ωr
C.ω2r
D.ω/r
Answer: B
65. The product of either force of couple with the arm of the couple is called
A.Resultant couple
B.Moment of the forces
C.Resulting couple
D.Moment of the couple
Answer: D
66. The moment of a force
A.Is the turning effect produced by a force, on the body, on which it acts
B.Is equal to the product of force acting on the body and the perpendicular distance of a point and the line of action of the force
C.Is equal to twice the area of the triangle, whose base is the line representing the force and whose vertex is the point, about which the moment is taken
D.All of the above
Answer: D
67. A heavy string attached at two ends at same horizontal level and when central dip is very small approaches the following curve
A.Circular arc
B.Parabola
C.Hyperbola
D.Elliptical
Answer: B
68. The centre of gravity a T-section 100 mm × 150 mm × 50 mm from its bottom is
A.50 mm
B.75 mm
C.87.5 mm
D.125 mm
Answer: C
69. Kinetic friction is the
A.Tangent of angle between normal reaction and the resultant of normal reaction and the limiting friction
B.Ratio of limiting friction and normal reaction
C.The friction force acting when the body is just about to move
D.The friction force acting when the body is in motion
Answer: D
70. According to Newton’s first law of motion,
A. Everybody continues in its state of rest or of uniform motion, in a straight line, unless it is acted upon by some external force
B. The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction, in which the force acts
C. To every action, there is always an equal and opposite reaction
D. None of the above
Answer: A
71. Which of the following is not a vector quantity?
A.Weight
B.Velocity
C.Acceleration
D.Force
Answer: A
72. The mechanical advantage of a lifting machine is the ratio of
A.Distance moved by effort to the distance moved by load
B.Load lifted to the effort applied
C.Output to the input
D.All of the above
Answer: B
73. From a circular plate of diameter 6 cm is cut out a circle whose diameter is a radius of the plate. Find the e.g. of the remainder from the centre of circular plate
A.0.5 cm
B.1.0 cm
C.1.5 cm
D.2.5 cm
Answer: A
74. In ideal machines, mechanical advantage is __________ velocity ratio.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: A
75. Frictional force encountered after commencement of motion is called
A.Limiting friction
B.Kinematic friction
C.Frictional resistance
D.Dynamic friction
Answer: D
76. The centre of gravity of a right circular solid cone is at a distance of _________ from its base, measured along the vertical axis.(where h = Height of a right circular solid cone.)
A.h/2
B.h/3
C.h/4
D.h/6
Answer: C
77. A particle inside a hollow sphere of radius r, having coefficient of friction µ can rest up to height of
A.r/2
B.r/A
C.r/3
D.0.134 r
Answer: D
78. Which of the following statement is incorrect?
A.A force acting in the opposite direction to the motion of the body is called force of friction
B.The ratio of the limiting friction to the normal reaction is called coefficient of friction
C.A machine whose efficiency is 100% is known as an ideal machine
D.The velocity ratio of a machine is the ratio of load lifted to the effort applied
Answer: D
79. A sample of metal weighs 219 gms in air, 180 gms in water, 120 gms in an unknown fluid. Then which is correct statement about density of metal
A.Density of metal can’t be determined
B.Metal is twice as dense as water
C.Metal will float in water
D.Metal is twice as dense as unknown fluid
Answer: A
80. The centre of percussion is below the centre of gravity of the body and is at a distance equal to
A.h/kG
B.h2/kG
C.kG2/h
D.h × kG
Answer: C
81. A cable with a uniformly distributed load per horizontal meter run will take the following shape
A.Straight line
B.Parabola
C.Hyperbola
D.Elliptical
Answer: B
82. When a body falls freely under gravitational force, it possesses __________ weight.
A.No
B.Minimum
C.Maximum
D.None of these
Answer: A
83. A body moves, from rest with a constant acceleration of 5 m per sec. The distance covered in 5 sec is most nearly
A.38 m
B.62.5 m
C.96 m
D.124 m
Answer: B
84. When the lift is moving upwards with some acceleration, the pressure exerted by a man is __________ to its acceleration.
A.Directly proportional
B.Inversely proportional
C.Cube root
D.None of these
Answer: A
85. Limiting force of friction is the
A.Tangent of angle between normal reaction and the resultant of normal reaction and limiting friction
B.Ratio of limiting friction and normal reaction
C.The friction force acting when the body is just about to move
D.The friction force acting when the body is in motion
Answer: C
86. A spherical body is symmetrical about its perpendicular axis. According to Routh’s rule, the moment of inertia of a body about an axis passing through its centre of gravity is (where, M = Mass of the body, and S = Sum of the squares of the two semi-axes.)
A.MS/3
B.MS/4
C.MS/5
D.None of these
Answer: C
87. The resultant of the following three couples 20 kg force, 0.5 m arm, +ve sense 30 kg force, 1 m arm, -ve sense 40 kg force, 0.25 m arm, +ve sense having arm of 0.5 m will be
A.20 kg, -ve sense
B.20 kg, + ve sense
C.10 kg, + ve sense
D.10 kg, -ve sense
Answer: A
88. In a framed structure, as shown in the below figure, the force in the member BC is
A.W/√3 (compression)
B.W/√3 (tension)
C.2W/√3 (compression)
D.2W/√3 (tension)
Answer: D
89. For any system of coplanar forces, the condition of equilibrium is that the
A.Algebraic sum of the horizontal components of all the forces should be zero
B.Algebraic sum of the vertical components of all the forces should be zero
C.Algebraic sum of moments of all the forces about any point should be zero
D.All of the above
Answer: D
90. D’ Alembert’s principle is used for
A.Reducing the problem of kinetics to equivalent statics problem
B.Determining stresses in the truss
C.Stability of floating bodies
D.Designing safe structures
Answer: A
91. Two bodies of masses m1 and m2 are hung from the ends of a rope, passing over a frictionless pulley as shown in the figure below. The acceleration of the string will be
A.g (m1 – m2)/(m1 + m2)
B.2g (m1 – m2)/(m1 + m2)
C.g (m1 + m2)/(m1 – m2)
D.2g (m1 + m2)/(m1 – m2)
Answer: A
92. The velocity ratio of a differential wheel and axle with ‘D’ as the diameter of effort wheel and d1 and d2 as the diameters of larger and smaller axles respectively, is
A.D/(d₁ + d₂)
B.D/(d₁ – d₂)
C.2D/(d₁ + d₂)
D.2D/(d₁ – d₂)
Answer: D
93. Which of the following is not the unit of power?
A.kW (kilowatt)
B.hp (horse power)
C.kcal/sec
D.kcal/kg sec
Answer: D
94. Non-coplanar non-concurrent forces are those forces which
A.Meet at one point, but their lines of action do not lie on the same plane
B.Do not meet at one point and their lines of action do not lie on the same plane
C.Do not meet at one point but their lines of action lie on the same plane
D.None of the above
Answer: B
95. The unit of force in S.I. units is
A.kilogram
B.Newton
C.Watt
D.Dyne
Answer: B
96. A number of forces acting at a point will be in equilibrium, if
A.All the forces are equally inclined
B.Sum of all the forces is zero
C.Sum of resolved parts in the vertical direction is zero (i.e. ∑V = 0)
D.None of these
Answer: C
97. The weight of a body is due to
A.Gravitational pull exerted by the earth
B.Forces experienced by body in atmosphere
C.Force of attraction experienced by particles
D.Gravitational force of attraction towards the centre of the earth
Answer: D
98. The efficiency of a lifting machine is the ratio of
A.Output to the input
B.Work done by the machine to the work done on the machine
C.Mechanical advantage to the velocity ratio
D.All of the above
Answer: D
99. According to principle of moments
A. If a system of coplanar forces is in equilibrium, then their algebraic sum is zero
B. If a system of coplanar forces is in equilibrium, then the algebraic sum of their moments about any point in their plane is zero
C. The algebraic sum of the moments of any two forces about any point is equal to moment of the resultant about the same point
D. Positive and negative couples can be balanced
Answer: B
100. Moment of inertia of a triangular section of baseB.and height (h) about an axis passing through its vertex and parallel to the base, is __________ than that passing through its C.G. and parallel to the base.
A.Nine times
B.Six times
C.Four times
D.Two times
Answer: A
101. A trolley wire weighs 1.2 kg per meter length. The ends of the wire are attached to two poles 20 meters apart. If the horizontal tension is 1500 kg find the dip in the middle of the span
A.2.5 cm
B.3.0 cm
C.4.0 cm
D.5.0 cm
Answer: C
102. The algebraic sum of the resolved parts of a number of forces in a given direction is equal to the resolved part of their resultant in the same direction. This is known as
A.Principle of independence of forces
B.Principle of resolution of forces
C.Principle of transmissibility of forces
D.None of these
Answer: B
103. A particle moves along a straight line such that distance (x) traversed in ‘t’ seconds is given by x = t² (t – 4), the acceleration of the particle will be given by the equation
A.6t² – 8t
B.3t² + 2t
C.6f – 8
D.6f – 4
Answer: C
104. The minimum force required to slide a body of weight ‘W’ on a rough horizontal plane is
A.W sinθ
B.W cosθ
C.W tanθ
D.None of these
Answer: C
105. The maximum frictional force which comes into play when a body just begins to slide over another surface is called
A.Limiting friction
B.Sliding friction
C.Rolling friction
D.Kinematic friction
Answer: A
106. The motion of a particle round a fixed axis is
A.Translatory
B.Rotary
C.Circular
D.Translatory as well as rotary
Answer: C
107. The C.G. of a right circular solid cone of height h lies at the following distance from the base
A.h/2
B.J/3
C.h/6
D.h/4
Answer: D
108. Which of the following statement is correct?
A.The kinetic energy of a body during impact remains constant
B.The kinetic energy of a body before impact is equal to the kinetic energy of a body after impact
C.The kinetic energy of a body before impact is less than the kinetic energy of a body after impact
D.The kinetic energy of a body before impact is more than the kinetic energy of a body after impact
Answer: D
109. A pair of smith’s tongs is an example of the lever of
A.Zeroth order
B.First order
C.Second order
D.Third order
Answer: C
110. Moment of inertia of a circular section about its diameterD.is
A.πd3/16
B.πd3/32
C.πd4/32
D.πd4/64
Answer: D
111. The forces, which meet at one point, but their lines of action do not lie in a plane, are called
A.Coplanar non-concurrent forces
B.Non-coplanar concurrent forces
C.Non-coplanar non-concurrent forces
D.Intersecting forces
Answer: B
112. The resultant of two forces P and Q acting at an angle θ is
A.√(P² + Q² + 2PQ sinθ)
B.√(P² + Q² + 2PQ cosθ)
C.√(P² + Q² – 2PQ cosθ)
D.√(P² + Q² – 2PQ tanθ)
Answer: B
113. Center of percussion is
A.The point of C.G.
B.The point of metacenter
C.The point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis
D.Point of suspension
Answer: C
114. The static friction
A.Bears a constant ratio to the normal reaction between the two surfaces
B.Is independent of the area of contact, between the two surfaces
C.Always acts in a direction, opposite to that in which the body tends to move
D.All of the above
Answer: D
115. Least force required to draw a body up the inclined plane is W sin (plane inclination + friction angle) applied in the direction
A.Along the plane
B.Horizontally
C.Vertically
D.At an angle equal to the angle of friction to the inclined plane
Answer: D
116. The law of motion involved in the recoil of gun is
A.Newton’s first law of motion
B.Newton’s second law of motion
C.Newton’s third law of motion
D.None of these
Answer: C
117. A circular hole of 50 mm diameter is cut out from a circular disc of 100 mm diameter as shown in the below figure. The center of gravity of the section will lie
A.In the shaded area
B.In the hole
C.At ‘O’
D.None of these
Answer: A
118. A semicircular disc rests on a horizontal surface with its top flat surface horizontal and circular portion touching down. The coefficient of friction between semi circular disc and horizontal surface is µ. This disc is to be pulled by a horizontal force applied at one edge and it always remains horizontal. When the disc is about to start moving, its top horizontal force will
A.Remain horizontal
B.Slant up towards direction of pull
C.Slant down towards direction of pull
D.None of the above
Answer: C
119. Which of the following statement is correct?
A.The periodic time of a particle moving with simple harmonic motion is the time taken by a particle for one complete oscillation
B.The periodic time of a particle moving with simple harmonic motion is directly proportional to its angular velocity
C.The velocity of the particle moving with simple harmonic motion is zero at the mean position
D.The acceleration of the particle moving with simple harmonic motion is maximum at the mean position
Answer: A
120. In ideal machines
A.Mechanical advantage is greater than velocity ratio
B.Mechanical advantage is equal to velocity ratio
C.Mechanical advantage is less than velocity ratio
D.Mechanical advantage is unity
Answer: B
121. The forces, whose lines of action are parallel to each other and act in the same directions, are known as
A.Coplanar concurrent forces
B.Coplanar non-concurrent forces
C.Like parallel forces
D.Unlike parallel forces
Answer: C
122. Two non-collinear parallel equal forces acting in opposite direction
A.Balance each other
B.Constitute a moment
C.Constitute a couple
D.Constitute a moment of couple
Answer: C
123. If the body falls freely under gravity, then the gravitational acceleration is taken as
A.+8.9 m/s2
B.-8.9 m/s2
C.+9.8 m/s2
D.-9.8 m/s2
Answer: C
124. The center of gravity of a triangle lies at the point of
A.Concurrence of the medians
B.Intersection of its altitudes
C.Intersection of bisector of angles
D.Intersection of diagonals
Answer: A
125. One joule means that
A.Work is done by a force of 1 N when it displaces a body through 1 m
B.Work is done by a force of 1 kg when it displaces a body through 1 m
C.Work is done by a force of 1 dyne when it displaces a body through 1 cm
D.Work is done by a force of 1 g when it displaces a body through 1 cm
Answer: A
126. On the ladder resting on the ground and leaning against a smooth vertical wall, the force of friction will be
A.Downwards at its upper end
B.Upwards at its upper end
C.Perpendicular to the wall at its upper end
D.Zero at its upper end
Answer: D
127. Which of the following are vector quantities?
A.Angular displacement
B.Angular velocity
C.Angular acceleration
D.All of these
Answer: D
128. Which of the following is the locus of a point that moves in such a manner that its distance from a fixed point is equal to its distance from a fixed line multiplied by a constant greater than one
A.Ellipse
B.Hyperbola
C.Parabola
D.Circle
Answer: B
129. In a framed structure, as shown in the below figure, the forces in the members AB and BC are respectively
A.√3. W (tensile) and 2W (compressive)
B.2W (tensile) and √3. W (compressive)
C.2√3. W (tensile) and 2√3. W (compressive)
D.None of the above
Answer: A
130. When a body of mass ‘m’ attains a velocity ‘v’ from rest in time ‘t’, then the kinetic energy of translation is
A.mv2
B.mgv2
C.0.5 mv2
D.0.5 mgv2
Answer: C
131. The M.I. of hollow circular section about a central axis perpendicular to section as compared to its M.I. about horizontal axis is
A.Same
B.Double
C.Half
D.Four times
Answer: B
132. The maximum efficiency of a lifting machine is
A.1/m
B.V.R./m
C.m/V.R.
D.1/(m × V.R.)
Answer: D
133. When trying to turn a key into a lock, following is applied
A.Coplanar force
B.Non-coplanar forces
C.Moment
D.Couple
Answer: D
134. Moment of inertia of a triangular section of baseB.and height (h) about an axis passing through its C.G. and parallel to the base, is
A.bh3/4
B.bh3/8
C.bh3/12
D.bh3/36
Answer: D
135. If a number of forces act simultaneously on a particle, it is possible
A.Not a replace them by a single force
B.To replace them by a single force
C.To replace them by a single force through C.G.
D.To replace them by a couple
Answer: B
136. If two bodies having masses m1 and m2 (m1>m2) have equal kinetic energies, the momentum of body having mass m1 is _________ the momentum of body having mass m2.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: C
137. Two coplanar couples having equal and opposite moments
A.Balance each other
B.Produce a couple and an unbalanced force
C.Are equivalent
D.Cannot balance each other
Answer: D
138. The center of gravity of a trapezium with parallel sides ‘a’ and ‘b’ lies at a distance of ‘y’ from the base ‘b’, as shown in the below figure. The value of ‘y’ is
A.h [(2a + b)/(a + b)]
B.(h/2) [(2a + b)/(a + b)]
C.(h/3) [(2a + b)/(a + b)]
D.(h/3) [(a + b)/(2a + b)]
Answer: C
139. Non-coplanar concurrent forces are those forces which
A.Meet at one point, but their lines of action do not lie on the same plane
B.Do not meet at one point and their lines of action do not lie on the same plane
C.Meet at one point and their lines of action also lie on the same plane
D.Do not meet at one point, but their lines of action lie on the same plane
Answer: A
140. In the equation of virtual work, following force is neglected
A.Reaction of any smooth surface with which the body is in contact
B.Reaction of a rough surface of a body which rolls on it without slipping
C.Reaction at a point or an axis, fixed in space, around which a body is constrained to turn
D.All of the above
Answer: D
141. The velocity of a particle moving with simple harmonic motion is _________ at the mean position.
A.Zero
B.Minimum
C.Maximum
D.None of these
Answer: C
142. If rain is falling in the opposite direction of the movement of a pedestrian, he has to hold his umbrella
A.More inclined when moving
B.Less inclined when moving
C.More inclined when standing
D.Less inclined when standing
Answer: D
143. The linear velocity of a body rotating at ω rad/s along a circular path of radius r is given by
A.ω/r
B.ω.r
C.ω2/r
D.ω2.r
Answer: B
144. The C.G. of a solid hemisphere lies on the central radius 3r
A.At distance — from the plane base 3r
B.At distance — from the plane base 3r
C.At distance — from the plane base 3r
D.At distance — from the plane base
Answer: D
145. The velocity ratio of a simple wheel and axle with D and d as the diameters of effort wheel and load axle, is
A.D + d
B.D – d
C.D × d
D.D / d
Answer: D
146. According to law of triangle of forces
A.Three forces acting at a point will be in equilibrium
B.Three forces acting at a point can be represented by a triangle, each side being proportional to force
C.If three forces acting upon a particle are represented in magnitude and direction by the sides of a triangle, taken in order, they will be in equilibrium
D.If three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two
Answer: C
147. The loss of kinetic energy during inelastic impact, is given by (where m1 = Mass of the first body,m2 = Mass of the second body, and u1 and u2 = Velocities of the first and second bodies respectively.)
A.[m₁ m₂/2(m₁ + m₂)] (u₁ – u₂)²
B.[2(m₁ + m₂)/m₁ m₂] (u₁ – u₂)²
C.[m₁ m₂/2(m₁ + m₂)] (u₁² – u₂²)
D.[2(m₁ + m₂)/m₁ m₂] (u₁² – u₂²)
Answer: A
148. If a suspended body is struck at the center of percussion, then the pressure on die axis passing through the point of suspension will be
A.Maximum
B.Minimum
C.Zero
D.Infinity
Answer: C
149. A couple produces
A.Translatory motion
B.Rotational motion
C.Combined translatory and rotational motion
D.None of the above
Answer: B
150. The resolved part of the resultant of two forces inclined at an angle ‘θ’ in a given direction is equal to
A.The algebraic sum of the resolved parts of the forces in the given direction
B.The sum of the resolved parts of the forces in the given direction
C.The difference of the forces multiplied by the cosine of θ
D.The sum of the forces multiplied by the sine of θ
Answer: A
151. The force, by which the body is attracted, towards the center of the earth, is called
A.Impulsive force
B.Mass
C.Weight
D.Momentum
Answer: C
152. The equivalent length of a simple pendulum which gives the same frequency as compound pendulum is
A.h/(kG² + h²)
B.(kG² + h²)/h
C.h²/(kG² + h²)
D.(kG² + h²)/h²
Answer: B
153. Moment of inertia of a rectangular section having widthB.and depthD.about an axis passing through its C.G. and parallel to the width (b), is
A.db³/12
B.bd³/12
C.db³/36
D.bd³/36
Answer: B
154. The length of a second’s pendulum is
A.94.9 cm
B.99.4 cm
C.100 cm
D.101 cm
Answer: B
155. The angle between two forces when the resultant is maximum and minimum respectively are
A.0° and 180°
B.180° and 0°
C.90° and 180°
D.90° and 0°
Answer: A
156. The velocity ratio of a first system of pulleys with 4 pulleys is
A.4
B.8
C.16
D.20
Answer: C
157. Which of the following is a scalar quantity?
A.Force
B.Speed
C.Velocity
D.Acceleration
Answer: B
158. The unit of angular velocity is
A.m/min
B.rad/s
C.Revolutions/min
D.BothB.and (C)
Answer: D
159. The force required to move the body up the plane will be minimum if it makes an angle with the inclined plane __________ the angle of friction.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: A
160. When a person, on a bicycle, drives round a curve, he has to lean __________ to maintain equilibrium.
A.Inward
B.Outward
C.Towards front
D.Towards back
Answer: A
161. The force induced in the string BC due to the load ‘W’ as shown in the below figure is
A.W sinθ
B.W cosθ
C.W tanθ
D.W cotθ
Answer: D
162. The center of gravity of a semi-circle lies at a distance of __________ from its base measured along the vertical radius.
A.3r/ 8
B.4r/ 3π
C.8r/3
D.3r/4π
Answer: B
163. The rate of doing work is known as
A.Potential energy
B.Kinetic energy
C.Power
D.None of these
Answer: C
164. The impact between two lead spheres is approximately equal to an __________ impact.
A.Elastic
B.Inelastic
C.Solid
D.None of these
Answer: B
165. The unit of angular acceleration is
A.N-m
B.m/s
C.m/s2
D.rad/s2
Answer: D
166. Which one of the following statements is not correct?
A.The tangent of the angle of friction is equal to coefficient of friction
B.The angle of repose is equal to angle of friction
C.The tangent of the angle of repose is equal to coefficient of friction
D.The sine of the angle of repose is equal to coefficient to friction
Answer: D
167. Coplanar concurrent forces are those forces which
A.Meet at one point, but their lines of action do not lie on the same plane
B.Do not meet at one point and their lines of action do not lie on the same plane
C.Meet at one point and their lines of action also lie on the same plane
D.Do not meet at one point, but their lines of action lie on the same plane
Answer: C
168. If ‘P’ is the force acting on the body, ‘m’ is the mass of the body and ‘a’ is the acceleration of the body, then according to Newton’s second law of motion,
A.P + m.a = 0
B.P – m.a = 0
C.P × m.a = 0
D.P/m.a = 0
Answer: B
169. If three forces acting in different planes can be represented by a triangle, these will be in
A.Non-equilibrium
B.Partial equilibrium
C.Full equilibrium
D.Unpredictable
Answer: A
170. The horizontal range of a projectile (R) is given by
A.R = u² cos2α/g
B.R = u² sin2α/g
C.R = u² cosα/g
D.R = u² sinα/g
Answer: B
171. A block of mass 20 kg lying on a rough horizontal plane is connected by a light string passing over a smooth pulley to another mass 5 kg, which can move freely in the Vertical direction, as shown in the below figure. The tension in the string will ___________ with the increase in coefficient of friction.
A.Increase
B.Decrease
C.Not be effected
D.None of these
Answer: A
172. Coplanar non-concurrent forces are those forces which __________ at one point, but their lines of action lie on the same plane.
A.Meet
B.Do not meet
C.Either ‘A’ or ‘B’
D.None of these
Answer: B
173. Which of the following do not have identical dimensions?
A.Momentum and impulse
B.Torque and energy
C.Torque and work
D.Moment of a force and angular momentum
Answer: D
174. In order to determine the effects of a force, acting on a body, we must know
A.Magnitude of the force
B.Line of action of the force
C.Nature of the force i.e. whether the force is push or pull
D.All of the above
Answer: D
175. A framed structure is perfect, if the number of members are __________ (2j – 3), where j is the number of joints.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: A
176. The ratio of limiting friction and normal reaction is known as
A.Coefficient of friction
B.Angle of friction
C.Angle of repose
D.Sliding friction
Answer: A
177. The bodies which rebound after impact are called
A.Inelastic bodies
B.Elastic bodies
C.Neither elastic nor inelastic bodies
D.None of these
Answer: B
178. The velocity of a particle (v) moving with simple harmonic motion, at any instant is given by (where, r = Amplitude of motion, and y = Displacement of the particle from mean position.)
A.ω.√(y² – r²)
B.ω.√(r² – y²)
C.ω².√(y² – r²)
D.ω².√(r² – y²)
Answer: B
179. If n = number of members and y = number of joints, then for a perfect frame, n = ?
A.1/2
B.2/3
C.3/2
D.2/4
Answer: B
180. A framed structure is imperfect, if the numbers of members are __________ (2j – 3).
A.Equal to
B.Less than
C.Greater than
D.EitherB.or (C)
Answer: D
181. The time of flight (t) of a projectile on a horizontal plane is given by
A.t = 2u. sinα/g
B.t = 2u. cosα/g
C.t = 2u. tanα/g
D.t = 2u/g.sinα
Answer: A
182. Which of the following is not the unit of distance?
A.Angstrom
B.Light year
C.Micron
D.Milestone
Answer: D
183. Two like parallel forces are acting at a distance of 24 mm apart and their resultant is 20 N. It the line of action of the resultant is 6 mm from any given force, the two forces are
A.15 N and 5 N
B.20 N and 5 N
C.15 N and 15 N
D.None of these
Answer: A
184. Which of the following are vector quantities?
A.Linear displacement
B.Linear velocity
C.Linear acceleration
D.All of these
Answer: D
185. Varingon’s theorem of moments states that if a number of coplanar forces acting on a particle are in equilibrium, then
A.Their algebraic sum is zero
B.Their lines of action are at equal distances
C.The algebraic sum of their moments about any point in their plane is zero
D.The algebraic sum of their moments about any point is equal to the moment of their resultant force about the same point
Answer: D
186. The possible loading in various members of framed structures are
A.Compression or tension
B.Buckling or shear
C.Shear or tension
D.All of the above
Answer: A
187. The acceleration of a particle moving with simple harmonic motion is __________ at the mean position.
A.Zero
B.Minimum
C.Maximum
D.None of these
Answer: A
188. Efficiency of a screw jack is given by (where α = Helix angle, and φ = Angle of friction.)
A.tan(α + φ)/tanα
B.tanα/tan (α + φ)
C.tan(α – φ)/tanα
D.None of these
Answer: B
189. The force induced in the string AB due to the load W, as shown in the below figure is
A.W sinθ
B.W cosθ
C.W secθ
D.W cosecθ
Answer: D
190. The unit of work or energy in S.I. units is
A.Newton
B.Pascal
C.Watt
D.Joule
Answer: D
191. The velocity ratio for the first system of pulleys is (where n is the number of pulleys.)
A.n
B.n²
C.2n
D.2n – 1
Answer: C
192. If a number of coplanar forces acting at a point be in equilibrium, the sum of clockwise moments must be __________ the sum of anticlockwise moments, about any point.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: A
193. Center of gravity of a thin hollow cone lies on the axis at a height of
A.One-fourth of the total height above base
B.One-third of the total height above base
C.One-half of the total height above base
D.Three-eighth of the total height above the base
Answer: B
194. Which of the following statement is correct in connection with projectiles?
A.A path, traced by a projectile in the space, is known as trajectory.
B.The velocity, with which a projectile is projected, is known as the velocity of projection.
C.The angle, with the horizontal, at which a projectile is projected, is known as angle of projection.
D.All of the above
Answer: D
195. A pendulum which executes one beat per second is known as
A.Simple pendulum
B.Compound pendulum
C.Torsional pendulum
D.Second’s pendulum
Answer: D
196. A single force and a couple acting in the same plane upon a rigid body
A.Balance each other
B.Cannot balance each other
C.Produce moment of a couple
D.Are equivalent
Answer: B
197. The forces which meet at one point, but their lines of action __________ on the same plane, are Known as non-coplanar concurrent forces.
A.Lie
B.Do not lie
C.Either A or B
D.None of these
Answer: B
198. During elastic impact, the relative velocity of the two bodies after impact is __________ the relative velocity of the two bodies before impact.
A.Equal to
B.Equal and opposite to
C.Less than
D.Greater than
Answer: D
199. A force is completely defined when we specify
A.Magnitude
B.Direction
C.Point of application
D.All of the above
Answer: D
200. The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction in which the force acts. This statement is known as
A.Newton’s first law of motion
B.Newton’s second law of motion
C.Newton’s third law of motion
D.None of these
Answer: B
201. The maximum efficiency of a screw jack is
A.(1 – sinφ)/(1 + sinφ)
B.(1 + sinφ)/(1 – sinφ)
C.(1 – tanφ)/(1 + tanφ)
D.(1 + tanφ)/(1 – tanφ)
Answer: A
202. The center of percussion of a solid cylinder of radius ‘r’ resting on a horizontal plane will be
A.r/2
B.2r/3
C.r/A
D.3r/2
Answer: D
203. The velocity ratio of a differential pulley block with D and d as the diameters of larger and smaller pulley, is
A.D/(D – d)
B.D/(D + d)
C.2D/(D – d)
D.2D/(D + d)
Answer: C
204. In a screw jack, the effort required to lower the load is __________ the effort required to raise the same load.
A.Less than
B.Equal to
C.More than
D.None of these
Answer: A
205. Tangent of angle of friction is equal to
A.Kinetic friction
B.Limiting friction
C.Angle of repose
D.Coefficient of friction
Answer: D
206. For a self locking machine, the efficiency must be
A.Equal to 50%
B.Less than 50%
C.Greater than 50%
D.100%
Answer: B
207. If the number of pulleys in a system is equal to its velocity ratio, then it is a __________ system of pulleys.
A.First
B.Second
C.Third
D.None of these
Answer: B
208. Effect of a force on a body depends upon
A.Magnitude
B.Direction
C.Position or line of action
D.All of the above
Answer: D
209. The ideal angle of banking provided on the curves on roads depends upon
A.Weight of the vehicle
B.(Velocity)2 of the vehicle
C.Nature of the road surface
D.Coefficient of friction between the road and vehicle contact point
Answer: B
210. Two blocks ‘A’ and ‘B’ of masses 150 kg and 50 kg respectively are connected by means of a string as shown in the below figure. The tension in all the three strings __________ be same.
A.Will
B.Will not
C.Either A or B
D.None of these
Answer: Option
211. The bellow figure shows the two equal forces at right angles acting at a point. The value of force ‘R’ acting along their bisector and in opposite direction is
A.P/2
B.2P
C.√2 × P
D.P/√2
Answer: C
212. A lead ball with a certain velocity is made to strike a wall, it falls down, but rubber ball of same mass and with same velocity strikes the same wall, it rebounds. Select the correct reason from the following:
A.Both the balls undergo an equal change in momentum
B.The change in momentum suffered by rubber ball is more than the lead ball
C.The change in momentum suffered by rubber ball is less than the lead ball
D.None of the above
Answer: B
213. In order to completely specify angular displacement by a vector, it must fix
A.Direction of the axis of rotation
B.Magnitude of angular displacement
C.Sense of angular displacement
D.All of these
Answer: D
214. The moment of inertia of a rectangular section 3 cm wide and 4 cm deep about X-X axis is
A.9 cm4
B.12 cm4
C.16 cm4
D.20 cm4
Answer: C
215. A framed structure is perfect if it contains members equal to (Where, n = number of joints in a frame)
A.2n³
B.2n
C.n²
D.3n²
Answer: A
216. The motion of a wheel of a car is
A.Purely translation
B.Purely rotational
C.Combined translation and rotational
D.None of these
Answer: C
217. A smooth cylinder lying on its convex surface remains in __________ equilibrium.
A.Stable
B.Unstable
C.Neutral
D.None of these
Answer: B
218. The velocity ratio in case of an inclined plane inclined at angle ‘θ’ to the horizontal and weight being pulled up the inclined plane by vertical effort is
A.sinθ
B.cosθ
C.tanθ
D.cosecθ
Answer: A
219. Forces are called concurrent when their lines of action meet in
A.One point
B.Two points
C.Plane
D.Perpendicular planes
Answer: A
220. The range of a projectile is maximum, when the angle of projection is
A.30°
B.45°
C.60°
D.90°
Answer: B
221. When a rigid body is suspended vertically, and it oscillates with a small amplitude under the action of the force of gravity, the body is known as
A.Simple pendulum
B.Compound pendulum
C.Torsional pendulum
D.Second’s pendulum
Answer: B
222. The potential energy of a vertically raised body is __________ the kinetic energy of a vertically falling body.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: A
223. The acceleration of a particle moving with simple harmonic motion, at any instant is given by
A.ω.y
B.ω2.y
C.ω2/y
D.ω3.y
Answer: B
224. The units of moment of inertia of mass are
A.kg-m²
B.m²/kg
C.kg/m²
D.kg/m
Answer: A
225. The linear acceleration A. of a body rotating along a circular path of radius (r) with an angular acceleration of α rad/s2, is
A.a = α/ r
B.a = α.r
C.a = r / α
D.None of these
Answer: B
226. Whenever a force acts on a body and the body undergoes a displacement, then
A.Work is said to be done
B.Power is being transmitted
C.Body has kinetic energy of translation
D.None of these
Answer: A
227. Which of the following is not the unit of energy?
A.kg m
B.kcal
C.Watt
D.Watt hours
Answer: C
228. The range of projectile will be maximum for a given velocity of projectile, when the angle of projection (α) is
A.β/2
B.30° + β/2
C.45° + β/2
D.60° + β/2
Answer: C
229. The power developed by a body acted upon by a torque ‘T’ Newton meter (N – m) and revolving at ω radian/s is given by
A.T.ω (in watts)
B.T.ω/60 (in watts)
C.T.ω/75 (in kilowatts)
D.T.ω/4500 (in kilowatts)
Answer: A
230. According to Lami’s theorem
A.The three forces must be equal
B.The three forces must be at 120° to each other
C.The three forces must be in equilibrium
D.If the three forces acting at a point are in equilibrium, then each force is proportional to the sine of the angle between the other two
Answer: D
231. Which of the following is not the unit of work, energy and heat?
A.kcal
B.kg-m
C.kW-hr
D.h.p
Answer: D
232. If the masses of both the bodies, as shown in the below figure, are doubled, then the acceleration in the string will be
A.Same
B.Half
C.Double
D.None of these
Answer: A
233. If a body is acted upon by a number of coplanar non-concurrent forces, it may
A.Rotate about itself without moving
B.Move in any one direction rotating about itself
C.Be completely at rest
D.All of these
Answer: D
234. The moment of inertia of a square of sideA.about an axis through its center of gravity is
A.a4/4
B.a4/8
C.a4/12
D.a4/36
Answer: C
235. A projectile is fired at an angle ‘θ’ to the vertical. Its horizontal range will be maximum when ‘θ’ is
A.0°
B.30°
C.45°
D.60°
Answer: C
236. The time of flight of a projectile on downward inclined plane depends upon
A.Angle of projection
B.Angle of inclination of the plane
C.BothA.and (B)
D.None of these
Answer: C
237. Which of the following is not a scalar quantity?
A.Mass
B.Volume
C.Density
D.Acceleration
Answer: D
238. The overturning of a vehicle on a level circular path can be avoided if the velocity of vehicle is __________ √(gra/h)
A.Less than
B.Greater than
C.Equal to
D.None of these
Answer: A
239. According to the law of moments, if a number of coplanar forces acting on a particle are in equilibrium, then
A.Their algebraic sum is zero
B.Their lines of action are at equal distances
C.The algebraic sum of their moments about any point in their plane is zero
D.The algebraic sum of their moments about any point is equal to the moment of their resultant force about the same point
Answer: C
240. When the spring of a watch is wound, it will possess
A.Strain energy
B.Kinetic energy
C.Heat energy
D.Electrical energy
Answer: A
241. The velocity ratio for the third system of pulleys is
A.n
B.n²
C.2n
D.2n – 1
Answer: D
242. Dynamic friction as compared to static friction is
A.Same
B.More
C.Less
D.May be less of more depending on nature of surfaces and velocity
Answer: C
243. Mass moment of inertia of a thin rod about its one end is ___________ the mass moment of inertia of the same rod about its mid-point
A.Same as
B.Twice
C.Thrice
D.Four times
Answer: D
244. In the shown figure, if the angle of inclination of the plane is increased, then acceleration of the system will
A.Increase
B.Decrease
C.Remain the same
D.None of these
Answer: B
245. An ideal machine is one whose efficiency is
A.Between 60 and 70 %
B.Between 70 and 80%
C.Between 80 and 90%
D.100%
Answer: D
246. If a number of forces are acting at a point, their resultant is given by
A.(∑V)2 + (∑H)2
B.√[(∑V)2 + (∑H)2]
C.(∑V)2 +(∑H)2 +2(∑V)(∑H)
D.√[(∑V)2 +(∑H)2 +2(∑V)(∑H)]
Answer: B
247. The force applied on a body of mass 100 kg to produce an acceleration of 5 m/s2, is
A.20 N
B.100 N
C.500 N
D.None of these
Answer: C
248. Which of the following is not the unit of pressure?
A.kg/cm
B.Bar
C.Atmosphere
D.Newton
Answer: D
249. The maximum frictional force, which comes into play, when a body just begins to slide over the surface of the other body, is known as
A.Static friction
B.Dynamic friction
C.Limiting friction
D.Coefficient of friction
Answer: C
250. The principle of transmissibility of forces states that, when a force acts upon a body, its effect is
A.Same at every point on its line of action
B.Different at different points on its line of action
C.Minimum, if it acts at the center of gravity of the body
D.Maximum, if it acts at the center of gravity of the body
Answer: C
251. In a screw jack, the effort required to lift the load is given by (where W = Load lifted, α = Helix angle, and φ = Angle of friction.)
A.P = W tan (α – φ)
B.P = W tan (α + φ)
C.P = W tan (φ – α)
D.P = W cos (α + φ)
Answer: B 12.
252. The moment of inertia of a thin disc of mass ‘m’ and radius ‘r’, about an axis through its center of gravity and perpendicular to the plane of the disc is
A.mr2/2
B.mr2/4
C.mr2/6
D.mr2/8
Answer: A
253. If a rigid body is in equilibrium under the action of three forces, then
A.These forces are equal
B.The lines of action of these forces meet in a point
C.The lines of action of these forces are parallel
D.BothB.andC.above
Answer: D
254. The matter contained in a body, is called
A.Impulsive force
B.Mass
C.Weight
D.Momentum
Answer: B
255. Moment of inertia is the
A.Second moment of force
B.Second moment of area
C.Second moment of mass
D.All of these
Answer: D
256. Joule is the unit of
A.Force
B.Work
C.Power
D.Velocity
Answer: B
257. The coefficient of friction depends on
A.Area of contact
B.Shape of surfaces
C.Strength of surfaces
D.Nature of surface
Answer: D
258. In a framed structure, as shown in the below figure, the force in the member AB is __________ the force in member AC.
A.Half
B.Equal to
C.Double
D.None of these
Answer: A
259. The velocity ratio of a single purchase crab winch can be increased by
A.Increasing the length of the handle
B.Increasing the radius of the load drum
C.Increasing the number of teeth of the pinion
D.All of the above
Answer: A
260. Two balls of equal mass and of perfectly elastic material are lying on the floor. One of the balls with velocity ‘v’ is made to strike the second ball. Both the balls after impact will move with a velocity
A.v
B.v/2
C.v/4
D.v/8
Answer: B
261. Moment of inertia of a circular section about an axis perpendicular to the section is
A.πd3/16
B.πd3/32
C.πd4/32
D.πd4/64
Answer: C
262. A redundant frame is also called __________ frame.
A.Perfect
B.Imperfect
C.Deficient
D.None of these
Answer: B
263. Tension in the cable supporting a lift is more when the lift is moving __________ with an acceleration.
A.Upwards
B.Downwards
C.Horizontal
D.None of these
Answer: A
264. The unit of work in S.I. units is
A.Newton
B.erg
C.kg-m
D.joule
Answer: D
265. If the gravitational acceleration at any place is doubled, then the weight of a body will be
A.g/2
B.g
C.√2.g
D.2g
Answer: D
266. The moment of inertia of a sphere of mass ‘m’ and radius ‘r’, about an axis tangential to it, is
A.2mr2/3
B.2mr2/5
C.7mr2/3
D.7mr2/5
Answer: D
267. The center of gravity of a quadrant of a circle lies along its central radius (r) at a distance of
A.0.5 r
B.0.6 r
C.0.7 r
D.0.8 r
Answer: B
268. The unit of moment of inertia of an area is
A.kg-m2
B.kg-m-s2
C.kg/m2
D.m4
Answer: D
269. When a body of mass moment of inertia ‘I’ (about a given axis) is rotated about that axis with an angular velocity to, then the kinetic energy of rotation is
A.Iω
B.Iω2
C.0.5 Iω
D.0.5 Iω2
Answer: D
270. In a single threaded worm and worm wheel, the number of teeth on the worm is 50. The diameter of the effort wheel is 100 mm and that of load drum is 50 mm. The velocity ratio is
A.50
B.100
C.200
D.400
Answer: B
271. One joule is equal to
A.0.1 N-m
B.1 N-m
C.10 N-m
D.100 N-m
Answer: B
272. A differential pulley block has larger and smaller diameters of 100 mm and 80 mm respectively. Its velocity ratio is
A.5
B.10
C.20
D.40
Answer: B
273. A body will begin to move down an inclined plane if the angle of inclination of the plane is _________ the angle of friction.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: C
274. The friction experienced by a body, when in motion, is known as
A.Rolling friction
B.Dynamic friction
C.Limiting friction
D.Static friction
Answer: B
275. Mass moment of inertia of a uniform thin rod of mass M and length (l) about its mid-point and perpendicular to its length is
A.(2/3) Ml²
B.(1/3) Ml²
C.(3/4) Ml²
D.(1/12) Ml²
Answer: D
276. If a given force (or a given system of forces) acting on a body __________ the position of the body, but keeps it in equilibrium, then its effect is to produce internal stress in the body.
A.Change
B.Does not change
C.Changes periodically
D.None of these
Answer: B
277. One end of a helical spring is fixed while the other end carries the load W which moves with simple harmonic motion. The frequency of motion is given by (where δ = Deflection of the spring.)
A.2π. √(g/δ)
B.1/2π. √(g/δ)
C.2π. √(δ/g)
D.1/2π. √(δ/g)
Answer: B
278. If tension in the cable supporting a lift moving downwards is half the tension when it is moving upwards, the acceleration of the lift is
A.g/2
B.g/3
C.g/4
D.None of these
Answer: D
279. The friction experienced by a body, when at rest, is known as
A.Static friction
B.Dynamic friction
C.Limiting friction
D.Coefficient of friction
Answer: A
280. The unit of force in S.I. system of units is
A.Dyne
B.Kilogram
C.Newton
D.Watt
Answer: C
281. One kg force is equal to
A.7.8 N
B.8.9 N
C.9.8 N
D.12 N
Answer: C
282. The resultant of the two forces ‘P’ and ‘Q’ is ‘R’. If ‘Q’ is doubled, the new resultant is perpendicular to ‘P’. Then
A.P = Q
B.Q = R
C.Q = 2R
D.None of these
Answer: B
283. The amplitude is always __________ radius of the circle.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: A
284. The moment of the force ‘P’ about ‘O’ as shown in the below figure is
A.P × OA
B.P × OB
C.P × OC
D.P × AC
Answer: C
285. The process of finding out the resultant force is called __________ of forces.
A.Composition
B.Resolution
C.Decomposition
D.None of these
Answer: A
286. Which of the following is an equation of linear motion?(where, u and v = Initial and final velocity of the body, a = Acceleration of the body, and s = Displacement of the body in time t seconds.)
A.v = u + a.t
B.s = u.t + ½ a.t2
C.v2 = u2 + 2a.s
D.All of these
Answer: D
287. Moment of inertia of a hollow circular section, as shown in the below figure about X-axis, is
A.π/16 (D² – d²)
B.π/16 (D³ – d³)
C.π/32 (D⁴ – d⁴)
D.π/64 (D⁴ – d⁴)
Answer: D
288. The forces which do not meet at one point and their lines of action do not lie on the same plane are known as
A.Coplanar concurrent forces
B.Coplanar non-concurrent forces
C.Non-coplanar concurrent forces
D.None of these
Answer: D
289. Concurrent forces are those forces whose lines of action
A.Lie on the same line
B.Meet at one point
C.Meet on the same plane
D.None of these
Answer: B
290. The moment of inertia of a solid cylinder of mass ‘m’, radius ‘r’ and length ‘l’ about the longitudinal axis or polar axis is
A.mr2/2
B.mr2/4
C.mr2/6
D.mr2/8
Answer: A
291. According to parallel axis theorem, the moment of inertia of a section about an axis parallel to the axis through center of gravity (i.e. IP) is given by(where, A = Area of the section, IG = Moment of inertia of the section about an axis passing through its C.G., and h = Distance between C.G. and the parallel axis.)
A.IP = IG + Ah2
B.IP = IG – Ah2
C.IP = IG / Ah2
D.IP = Ah2 / IG
Answer: A
291. The law of the machine is (where P = Effort applied to lift the load, m = A constant which is equal to the slope of the line, W = Load lifted, and C = Another constant which represents the machine friction.)
A.P = mW – C
B.P = m/W + C
C.P = mW + C
D.P = C – mW
Answer: C
292. The wheels of a moving car possess
A.Potential energy only
B.Kinetic energy of translation only
C.Kinetic energy of rotation only
D.Kinetic energy of translation and rotation both
Answer: D
293. The resultant of two equal forces ‘P’ making an angle ‘θ’, is given by
A.2P sinθ/2
B.2P cosθ/2
C.2P tanθ/2
D.2P cotθ/2
Answer: B
294. The coefficient of restitution for inelastic bodies is
A.Zero
B.One
C.Between zero and one
D.More than one
Answer: A
295. If a number of forces are acting at a point, their resultant will be inclined at an angle ‘θ’ with the horizontal, such that
A.tanθ = ΣH/ΣV
B.tanθ = ΣV/ΣH
C.tanθ = ΣV × ΣH
D.tanθ = √(ΣV + ΣH)
Answer: B
296. The periodic time of a particle with simple harmonic motion is _________ proportional to the angular velocity.
A.Directly
B.Inversely
C.Square root
D.None of these
Answer: B
297. The efficiency of a screw jack is maximum, when (where α = Helix angle, and φ = Angle of friction.)
A.α = 45° + φ/2
B.α = 45° – φ/2
C.α = 90° + φ
D.α = 90° – φ
Answer: B
298. The total motion possessed by a body, is called
A.Impulsive force
B.Mass
C.Weight
D.Momentum
Answer: D 299. A screw jack used for lifting the loads is
A.A reversible machine
B.A non-reversible machine
C.An ideal machine
D.None of these
Answer: B
300. If u1 and u2 are the velocities of two moving bodies in the same direction before impact and v1 and v2 are their velocities after impact, then coefficient of restitution is given by
A.(v1 – v2)/(u1 – u2)
B.(v₂ – v₁)/(u1 – u2)
C.(u1 – u2)/(v1 – v2)
D.(u₂ + u₁)/(v₂ + v₁)
Answer: B
301. Work done is said to be zero, when
A.Some force acts on a body, but displacement is zero
B.No force acts on a body but some displacement takes place
C.EitherA.or (B)
D.None of the above
Answer: C
302. The range of projectile on a downward inclined plane is ________ the range on upward inclined plane for the same velocity of projection and angle of projection.
A.Less than
B.More than
C.Equal to
D.None of These
Answer: B
303. The point, through which the whole weight of the body acts, irrespective of its position, is known as
A.Moment of inertia
B.Center of gravity
C.Center of percussion
D.Center of mass
Answer: B
304. The total energy possessed by a system of moving bodies
A.Is constant at every instant
B.Varies from point to point
C.Is maximum in the start and minimum at the end
D.Is minimum in the start and maximum at the end
Answer: A
305. The acceleration of a body sliding down an inclined surface is
A.g sinθ
B.g cosθ
C.g tanθ
D.None of these
Answer: A
306. A force while acting on a body may
A.Change its motion
B.Balance the forces, already acting on it
C.Give rise to the internal stresses in it
D.All of these
Answer: D
307. A machine having an efficiency less than 50%, is known as
A.Reversible machine
B.Non-reversible machine
C.Neither reversible nor non-reversible machine
D.Ideal machine
Answer: B
308. Static friction is always __________ dynamic friction.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: C
309. In the shown figure, the tension (T) in the string will be
A.m₁. m₂. g/(m₁ + m₂)
B.2m₁. m₂. g/(m₁ + m₂)
C.(m₁ + m₂)/ m₁. m₂. g
D.(m₁ + m₂)/2m₁. m₂. g
Answer: B
310. A body of weight ‘W’ is required to move up on rough inclined plane whose angle of inclination with the horizontal is ‘α’. The effort applied parallel to the plane is given by (where μ = tanφ = Coefficient of friction between the plane and the body.)
A.P = W tanα
B.P = W tan (α + φ)
C.P = W (sinα + μcosα)
D.P = W (cosα + μsinα)
Answer: C
311. A smooth cylinder lying on a __________ is in neutral equilibrium.
A.Curved surface
B.Convex surface
C.Horizontal surface
D.None of these
Answer: C
312. The unit of energy in S.I. units is
A.Dyne
B.Watt
C.kg-m
D.Joule
Answer: D
313. A ladder is resting on a rough ground and leaning against a smooth vertical wall. The force of friction will act
A.Downward at its upper end
B.Upward at its upper end
C.Zero at its upper end
D.Perpendicular to the wall at its upper end
Answer: C
314. The periodic time of one oscillation for a simple pendulum is (where l = Length of the pendulum.)
A.(1/2π). √(l/g)
B.(1/2π). √(g/l)
C.2π. √(l/g)
D.None of these
Answer: C
315. The total momentum of a system of masses (i. e. moving bodies) in any one direction remains constant, unless acted upon by an external force in that direction. This statement is called
A.Newton’s first law of motion
B.Newton’s second law of motion
C.Principle of conservation of energy
D.Principle of conservation of momentum
Answer: D
316. The moment of inertia of a thin spherical shell of mass m and radius r, about its diameter is
A.mr2/3
B.2mr2/3
C.2mr2/5
D.3mr2/5
Answer: B
317. The moment of inertia of a solid cone of mass ‘m’ and base radius ‘r’ about its vertical axis is
A.3mr2/5
B.3mr2/10
C.2mr2/5
D.4mr2/5
Answer: B
318. If the resultant of two equal forces has the same magnitude as either of the forces, then the angle between the two forces is
A.30°
B.60°
C.90°
D.120°
Answer: D
319. In actual machines, mechanical advantage is _________ velocity ratio.
A.Equal to
B.Less than
C.Greater than
D.None of these
Answer: B
320. The moment of inertia of a solid sphere of mass ‘m’ and radius ‘r’ is
A.2mr2/3
B.2mr2/5
C.mr2
D.mr2/2
Answer: B
321. Moment of inertia of a rectangular section having widthB.and depthD.about an axis passing through its C.G. and parallel to the depth (d), is
A.db³/12
B.bd³/12
C.db³/36
D.bd³/36
Answer: A
322. The unit of power in S.I. units is
A.Horsepower
B.Joule
C.Watt
D.kg-m
Answer: C
323. The maximum height of a projectile on a horizontal plane, is
A.u² sin²α/2g
B.u² cos²α/2g
C.u² sin²α/g
D.u² cos²α/g
Answer: A
324. One watt is equal to
A.0.1 joule/s
B.1 joule/s
C.10 joules/s
D.100 joules/s
Answer: B
325. The moment of inertia of a square of side a about its diagonal is
A.a2/8
B.a3/12
C.a4/12
D.a4/16
Answer: C
326. The maximum acceleration of a particle moving with simple harmonic motion is
A.ω
B.ωr
C.ω2r
D.ω/r
Answer: C
327. The rate of change of displacement of a body is called
A.Velocity
B.Acceleration
C.Momentum
D.None of these
Answer: A
328. The maximum mechanical advantage of a lifting machine is
Historical evidence since World War II has shown that the theory of comparative cost does not sufficiently explain the trend and pattern of actual international trade.
If we divide the world into two blocks, i.e., (a) the developed countries and (b) the less developed countries; and the commodities into two groups, i.e., (a) the manufactured goods and (b) the primary goods, then on the basis of the comparative cost principle we expect that
(i) The developed countries have a comparative advantage over the less developed countries in manufactured goods relative to primary goods;
(ii) The larger and growing part of the world trade is between developed and less developed countries; and
(iii) The developed countries produce and export manufactured goods in exchange for primary goods from less developed countries.
But, the actual pattern of world is not in accordance with the theory of comparative cost. The following features of world trade make this clear.
(i) The largest part of world trade is among the developed countries themselves, rather than between developed countries and the less developed countries.
(ii) Although, in accordance with the theory of comparative cost, the developed countries, on balance, export manufactured goods to the less developed countries in exchange for primary production, but the largest part of world trade is the intra-industry exchange of manufactures among the developed countries themselves.
(iii) As against the comparative cost principle, export of manufactures from less developed countries are the fast growing part of world trade, although their absolute share is still small.
(iv) Economics of scale, which arise from the division of labour and product differentiation, imply that trade between countries with modest comparative cost differences will be largely intra- industry, and that trade between countries with substantial comparative cost differences will be largely interred-in- dusty.
A notable feature of trade among the developed countries is that it is a large and growing volume of intra-industry trade, both absolutely and relative to inter-industry trade.
2. The torque transmitted by a solid shaft of diameter (D) is (where τ = Maximum allowable shear stress)
(A) π /4 × τ × D³
(B) π /16 × τ × D³
(C) π /32 × τ × D³
(D) π /64 × τ × D³
Answer: B
3. The torque transmitted by a hollow shaft of outer diameter (d₁) and inner diameter (d2) is (where, τ = Maximum allowable shear stress)
(A) π /4 × τ × (d₁⁴ – d⁴₂)/ d₁
(B) π /16 × τ × (d₁⁴ – d⁴₂)/ d₁
(C) π /32 × τ × (d₁⁴ – d⁴₂)/ d₁
(D) π /64 × τ × (d₁⁴ – d⁴₂)/ d₁
Answer: B
4. If Th is the torque resisting capacity of a hollow shaft and Ts is that of a solid shaft, of the same material, length and weight. Then,
(A) Th > Ts
(B) Th < Ts
(C) Th = Ts
(D) None of these
Answer: A
5. A cube subjected to three mutually perpendicular stress of equal intensity p expenses a volumetric strain
(A) 3p/ E × (2/m – 1)
(B) 3p/ E × (2 – m)
(C) 3p/ E × (1 – 2/m)
(D) E/ 3p × (2/m – 1)
Answer: C
6. The strain energy stored in a solid circular shaft subjected to shear stress (τ), is: (Where, G = Modulus of rigidity for the shaft material)
(A) τ²/ 2G × Volume of shaft
(B) τ/ 2G × Volume of shaft
(C) τ²/ 4G × Volume of shaft
(D) τ/ 4G × Volume of shaft
Answer: A
7. The strain energy stored in a solid circular shaft in torsion, subjected to shear stress (τ), is: (Where, G = Modulus of rigidity for the shaft material)
(A) τ²/ 2G × Volume of shaft
(B) τ/ 2G × Volume of shaft
(C) τ²/ 4G × Volume of shaft
(D) τ/ 4G × Volume of shaft
Answer: C
8. The stress induced in a body, when suddenly loaded, is _________ the stress induced when the same load is applied gradually.
(A) Equal to
(B) One-half
(C) Twice
(D) Four times
Answer: C
9. If Kh is the torque resisting capacity of a hollow shaft and Ks is that of a solid shaft, of the same material, length and weight. Then,
(A) Kh > Ks
(B) Kh < Ks
(C) Kh = Ks
(D) None of these
Answer: A
10. After reaching the yielding stage while testing a mild steel specimen, strain
(A) Becomes constant
(B) Starts decreasing
(C) Increases without any increase in load
(D) None of the above
Answer: C
STRENGTH of Materials Multiple Choice Questions
11. Principal planes are planes having
(A) Maximum shear stress
(B) No shear stress
(C) Minimum shear stress
(D) None of the above
Answer: B
12. If the slenderness ratio for a column is 100, then it is said to be a _________ column.
(A) Long
(B) Medium
(C) Short
(D) None of these
Answer: A
13. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum normal stress will be
(A) 400 MPa
(B) 500 MPa
(C) 900 MPa
(D) 1400 MPa
Answer: D
14. Young’s modulus of a wire is defined as the stress which will increase the length of wire compared to its original length by
(A) Half
(B) Same amount
(C) Double
(D) One-fourth
Answer: B
15. True stress strain-curve for materials is plotted between
(A) Load/original cross-sectional area and change in length/original length
(B) Load/ instantaneous cross-sectional area and loge (original area/ instantaneous area)
(C) Load/ instantaneous cross-sectional area and change in length/ original length
(D) Load/ instantaneous area and instantaneous area/original area
Answer: B
16. A hollow shaft of same cross-section area as compared to a solid shaft transmit
(A) Same torque
(B) Less torque
(C) More torque
(D) Unpredictable
Answer: C
17. A steel bar of 5 mm is heated from 25°C to 45°C and it is free to expand. The bar will induce
(A) No stress
(B) Shear stress
(C) Tensile stress
(D) Compressive stress
Answer: A
18. Two shafts ‘A’ and ‘B’ transmit the same power. The speed of shaft ‘A’ is 250 r.p.m. and that of shaft ‘B’ is 300 r.p.m.
(A) The shaft ‘B’ has the greater diameter
(B) The shaft ‘A’ has the greater diameter
(C) Both are of same diameter
(D) None of these
Answer: B
19. The intensity of stress which causes unit strain is called
(A) Unit mass
(B) Modulus of rigidity
(C) Bulk modulus
(D) Modulus of Elasticity
Answer: D
20. A thick cylindrical shell having ro and ri as outer and inner radii, is subjected to an internal pressure (p). The maximum tangential stress at the inner surface of the shell is
(A) (ro² – ri²)/ 2p ri²
(B) 2p ri²/ (ro² – ri²)
(C) p (ro² + ri²)/ (ro² – ri²)
(D) p (ro² – ri²)/ (ro² + ri²)
Answer: C
21. A vertical column has two moments of inertia (i.e. Ixx and Iyy ). The column will tend to buckle in the direction of the
(A) Axis of load
(B) Perpendicular to the axis of load
(C) Maximum moment of inertia
(D) Minimum moment of inertia
Answer: D
22. Strain energy is the
(A) Energy stored in a body when strained within elastic limits
(B) Energy stored in a body when strained up to the breaking of a specimen
(C) Maximum strain energy which can be stored in a body
(D) Proof resilience per unit volume of a material
Answer: A
23. The neutral axis of the cross-section a beam is that axis at which the bending stress is
(A) Zero
(B) Minimum
(C) Maximum
(D) Infinity
Answer: A
24. A composite bar made up of steel and copper bars of equal lengths are heated through 100°C. The stresses developed shall be
(A) Tensile in both the material
(B) Tensile in steel and compressive in copper
(C) Compressive in steel and tensile in copper
(D) Compressive in both the materials
Answer: D
25. Euler’s formula holds good only for
(A) Short columns
(B) Long columns
(C) Both short and long columns
(D) Weak columns
Answer: B
26. The bending moment at a point on a beam is the algebraic ________ of all the moments on either side of the point.
(A) Sum
(B) Difference
(C) Multiplication
(D) None of the above
Answer: A
27. The maximum diameter of the hole that can be punched from a plate of maximum shear stress 1/4th of its maximum crushing stress of punch, is equal to (where t = Thickness of the plate)
(A) t
(B) 2t
(C) 4t
(D) 8t
Answer: C
28. Within elastic limit, stress is
(A) Inversely proportional to strain
(B) Directly proportional to strain
(C) Square root of strain
(D) Equal to strain
Answer: B
29. Two closely coiled helical springs ‘A’ and ‘B’ are equal in all respects but the number of turns of spring ‘A’ is half that of spring ‘B’ The ratio of deflections in spring ‘A’ to spring ‘B’ is
(A) 1/8
(B) 1/4
(C) 1/2
(D) 2
Answer: C
30. The deformation per unit length is called
(A) Tensile stress
(B) Compressive stress
(C) Shear stress
(D) Strain
Answer: D
31. The shape of cantilever for uniformly distributed load will be
(A) Straight line
(B) Parabolic
(C) Elliptical
(D) Cubic
Answer: B
32. For a simply supported beam of length ‘l’, when a concentrated load W is applied in the center of the beam, the maximum deflection is
(A) 5WL³/ 384EI
(B) WL³/384EI
(C) WL³/ 348EI
(D) WL³/ 48EI
Answer: D
33. The point of contra flexure is a point where
(A) Shear force changes sign
(B) Shear force is maximum
(C) Bending moment changes sign
(D) Bending moment is maximum
Answer: C
34. The maximum stress produced in a bar of tapering section is at
(A) Smaller end
(B) Larger end
(C) Middle
(D) Anywhere
Answer: A
35. The ultimate tensile stress of mild steel compared to ultimate compressive stress is
(A) Same
(B) More
(C) Less
(D) Unpredictable
Answer: B
36. The energy stored in a body when strained within elastic limit is known as
(A) Resilience
(B) Proof resilience
(C) Strain energy
(D) Impact energy
Answer: C
37. Modular ratio of two materials is the ratio of
(A) Strains
(B) Stress and strain
(C) Shear stress and shear strain
(D) Moduli and elasticity
Answer: D
38. In compression test, the fracture in cast iron specimen would occur along
(A) The axis of load
(B) An oblique plane
(C) At right angles to the axis of specimen
(D) Would not occur
Answer: B
39. A coil is cut into two halves, the stiffness of cut coil will be
(A) Double
(B) Half
(C) Same
(D) None of these
Answer: A
40. The bending stress in a beam is _________ section modulus.
(A) Inversely proportional to two times
(B) Directly proportional to
(C) Inversely proportional to
(D) None of these
Answer: C
41. When shear force at a point is zero, then bending moment is _________ at that point.
(A) Zero
(B) Minimum
(C) Maximum
(D) Infinity
Answer: C
42. Elasticity of Mild Steel specimen is defined by
(A) Hooke’s law
(B) Yield point
(C) Plastic flow
(D) Proof stress
Answer: C
43. When a bar is cooled to -5°C, it will develop
(A) No stress
(B) Shear stress
(C) Tensile stress
(D) Compressive stress
Answer: C
44. If the radius of wire stretched by a load is doubled, then its Young’s modulus will be
(A) Doubled
(B) Halved
(C) Becomes four times
(D) None of the above
Answer: D
45. In order to know whether a column is long or short, we must know its
(A) Ultimate shear stress of the column
(B) Factor of safety
(C) Torque resisting capacity
(D) Slenderness ratio
Answer: D
46. A masonry dam may fail due to
(A) Tension in the masonry of the dam and its base
(B) Overturning of the dam
(C) Crushing of masonry at the base of the dam
(D) Any one of the above
Answer: D
47. Impact strength of a material is an index of its
(A) Toughness
(B) Tensile strength
(C) Capability of being cold worked
(D) Hardness
Answer: A
48. In order to prevent crushing of masonry at the base of the dam, the maximum stress should be __________ the permissible stress of the soil.
(A) Equal to
(B) Less than
(C) More than
(D) None of these
Answer: B
49. Volumetric strain for a rectangular specimen of length ‘l’, breadth ‘b’ and thickness ‘t’ subjected to a pull of ‘P’ is given by
(A) e (1 – 2m)
(B) e (1 – 2/m)
(C) e (m – 2)
(D) e (2/m – 1)
Answer: B
50. When a body is subjected to two equal and opposite pushes, as a result of which the body tends to reduce its length, then
(A) The stress and strain induced is compressive
(B) The stress and strain induced is tensile
(C) Both A and B is correct
(D) None of these
Answer: A
51. A thin cylindrical shell of diameter (d) and thickness (t) is subjected to an internal pressure (p). The ratio of longitudinal strain to volumetric strain is
(A) (m – 1)/ (2m – 1)
(B) (2m – 1)/ (m – 1)
(C) (m – 2)/ (3m – 4)
(D) (m – 2)/ (5m – 4)
Answer: D
52. Modulus of rigidity is defined as the ratio of
(A) Longitudinal stress to longitudinal strain
(B) Volumetric stress to volumetric strain
(C) Lateral stress to Lateral strain
(D) Shear stress to shear strain
Answer: D
53. In the torsion equation T/J = τ/r = Gθ/ L, the term J/R is called
(A) Shear modulus
(B) Section modulus
(C) Polar modulus
(D) None of these
Answer: C
54. Strain re-setters are used to
(A) Measure shear strain
(B) Measure linear strain
(C) Measure volumetric strain
(D) Relieve strain
Answer: B
55. When a rectangular beam is loaded transversely, the maximum compressive stress is developed on the
(A) Top layer
(B) Bottom layer
(C) Neutral axis
(D) Every cross-section
Answer: B
56. In a uniform bar, supported at one end in position, the maximum stress under self weight of bar shall occur at the
(A) Middle of bar
(B) Supported end
(C) Bottom end
(D) None of these
Answer: B
57. When both ends of a column are fixed, the effective length is
(A) Its own length
(B) Twice its length
(C) Half its length
(D) 1/√2 × its length
Answer: C
58. A composite shaft consisting of two stepped portions having spring constants K₁ and K₂ is held between two rigid supports at the ends. Its equivalent spring constant is
(A) K₁ K₂
(B) (K₁ + K₂)/ 2
(C) (K₁ + K₂)/ K₁ K₂
(D) K₁ K₂/ (K₁ + K₂)
Answer: A
59. Slenderness of a column is zero when
(A) Ends are firmly fixed
(B) Column is supported on all sides throughout the length
(C) Length is equal to radius of gyration
(D) Length is twice the radius of gyration
Answer: D
60. Resilience is the
(A) Energy stored in a body when strained within elastic limits
(B) Energy stored in a body when strained up to the breaking of the specimen maximum strain
(C) Energy which can be stored in a body
(D) None of the above
Answer: D
61. When a closely-coiled helical spring of mean diameter (D) is subjected to an axial load (W), the deflection of the spring (δ) is given by (where d = Diameter of spring wire, n = No. of turns of the spring, and C = Modulus of rigidity for the spring material)
(A) WD3n/Cd⁴
(B) 2WD3n/Cd⁴
(C) 4WD3n/Cd⁴
(D) 8WD3n/Cd⁴
Answer: D
62. Percentage reduction of area in performing tensile test on cast iron may be of the order of
(A) 50%
(B) 25%
(C) 0%
(D) 15%
Answer: C
63. For the beam shown in the below figure, the shear force diagram between A and B is
(A) A horizontal line
(B) A vertical line
(C) An inclined line
(D) A parabolic curve
Answer: D
64. When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the maximum normal stress is
(A) (σx/2) + (1/2) × √(σx² + 4 τ²xy)
(B) (σx/2) – (1/2) × √(σx² + 4 τ²xy)
(C) (σx/2) + (1/2) × √(σx² – 4 τ²xy)
(D) (1/2) × √(σx² + 4 τ²xy)
Answer: A
65. The materials which exhibit the same elastic properties in all directions are called
(A) Homogeneous
(B) Inelastic
(C) Isotropic
(D) Isentropic
Answer: C
66. Modulus of rigidity may be defined as the ratio of
(A) Linear stress to lateral strain
(B) Lateral strain to linear strain
(C) Linear stress to linear strain
(D) Shear stress to shear strain
Answer: D
67. The ratio of lateral strain to the linear strain within elastic limit is known as
(A) Young’s modulus
(B) Bulk modulus
(C) Modulus of rigidity
(D) Poisson’s ratio
Answer: D
68. In the below figure, the plastic range occurs
(A) Before point A
(B) Beyond point A
(C) Between points A and D
(D) Between points D and E
Answer: B
69. Shear modulus is the ratio of
(A) Linear stress to linear strain
(B) Linear stress to lateral strain
(C) Volumetric strain to linear strain
(D) Shear stress to shear strain
Answer: D
70. The ratio of elongation in a prismatic bar due to its own weight (W) as compared to another similar bar carrying an additional weight (W) will be
(A) 1 : 2
(B) 1 : 3
(C) 1 : 4
(D) 1 : 2.5
Answer: B
71. The weakest section of a diamond riveting is the section which passes through
(A) The first row
(B) The second row
(C) The central row
(D) One rivet hole of the end row
Answer: D
72. The shear force diagram for a simply supported beam carrying a uniformly distributed load of w per unit length, consists of
(A) One right angled triangle
(B) Two right angled triangles
(C) One equilateral triangle
(D) Two equilateral triangles
Answer: B
73. Hooke’s law holds good up to
(A) Yield point
(B) Limit of proportionality
(C) Breaking point
(D) Elastic limit
Answer: B
74. Which of the following statement is correct?
(A) The stress is the pressure per unit area
(B) The strain is expressed in mm
(C) Hook’s law holds good up to the breaking point
(D) Stress is directly proportional to strain within elastic limit
Answer: D
75. The property of a material which allows it to be drawn into a smaller section is called
(A) Plasticity
(B) Ductility
(C) Elasticity
(D) Malleability
Answer: B
76. The percentage reduction in area of a cast iron specimen during tensile test would be of the order of
(A) More than 50%
(B) 25-50%
(C) 10-25%
(D) Negligible
Answer: D
77. The deformation of a bar under its own weight is _________ the deformation, if the same body is subjected to a direct load equal to weight of the body.
(A) Equal to
(B) Half
(C) Double
(D) Quadruple
Answer: B
78. The ratio of maximum shear stress developed in a rectangular beam and a circular beam of the same cross-sectional area is
(A) 2/3
(B) 3/4
(C) 1
(D) 9/8
Answer: D
79. Formula based on IS codes is based on
(A) Straight line formula
(B) Euler’s formula
(C) Rankine’s formula
(D) Secant formula
Answer: D
80. Resilience of a material is considered when it is subjected to
(A) Frequent heat treatment
(B) Fatigue
(C) Creep
(D) Shock loading
Answer: D
81. The buckling load for a given column depends upon
(A) Area of cross-section of the column
(B) Length and least radius of gyration of the column
(C) Modulus of elasticity for the material of the column
(D) All of the above
Answer: D
82. The shear force at the center of a simply supported beam with a gradually varying load from zero at both ends to w per meter at the center, is
(A) Zero
(B) wl/4
(C) wl/2
(D) wl²/2
Answer: A
83. A riveted joint in which the number otrivets decrease from innermost to outer most rows is called
(A) Chain riveted joint
(B) Diamond riveted joint
(C) Crisscross riveted joint
(D) Zigzag riveted joint
Answer: B
84. A closely-coiled helical spring is cut into two halves. The stiffness of the resulting spring will be
(A) Same
(B) Double
(C) Half
(D) One-fourth
Answer: B
85. The torsional rigidity of a shaft is expressed by the
(A) Maximum torque it can transmit
(B) Number of cycles it undergoes before failure
(C) Elastic limit up to which it resists torsion, shear and bending stresses
(D) Torque required to produce a twist of one radian per unit length of shaft
Answer: D
86. The limit of eccentricity for no tensile conditions for a column of circular section of diameter (d) is
(A) d/4
(B) d/8
(C) d/12
(D) d/16
Answer: B
87. The property of a material by virtue of which a body returns to its original, shape after removal of the load is called
(A) Plasticity
(B) Elasticity
(C) Ductility
(D) Malleability
Answer: B
88. The state of stress at a point in a loaded member is shown in the below figure. The magnitude of maximum shear stress is
(A) 10 MPa
(B) 30 MPa
(C) 50 MPa
(D) 100 MPa
Answer: C
89. For a beam, as shown in the below figure, the deflection at C is (where E = Young’s modulus for the beam material, and I = Moment of inertia of the beam section.)
(A) Wl3/48 EI
(B) Wa²b²/3EIl
(C) [Wa/(a√3) x EIl] x (l² – a²)3/2
(D) 5Wl3/384 EI
Answer: B
90. A concentrated load is one which
(A) Acts at a point on a beam
(B) Spreads non-uniformly over the whole length of a beam
(C) Spreads uniformly over the whole length of a beam
(D) Varies uniformly over the whole length of a beam
Answer: A
91. The stress necessary to initiate yielding is
(A) Considerably greater than that necessary to continue it
(B) Considerably lesser than that necessary to continue it
(C) Greater than that necessary to stop it
(D) Lesser than that necessary to stop it
Answer: A
92. A lap joint is always in _________ shear.
(A) Single
(B) Double
(C) Both A and B
(D) None of these
Answer: A
93. When it is indicated that a member is elastic, it means that when force is applied, it will
(A) Not deform
(B) Be safest
(C) Stretch
(D) Not stretch
Answer: C
94. For a beam, as shown in the below figure, when the load W is applied in the center of the beam, the maximum deflection is
(A) Wl3 / 48EI
(B) 5Wl3 / 384EI
(C) Wl3 / 392EI
(D) Wl3 / 384EI
Answer: A
95. The relation between Young’s modulus (E), shear modulus (C) and bulk modulus (K) is given by
(A) E = 3K.C/(3K + C)
(B) E = 6K.C/(3K + C)
(C) E = 9K.C/(3K + C)
(D) E = 12K.C/(3K + C)
Answer: C
96. The distance between the centers of the rivets in adjacent rows of zigzag riveted joint is known as
(A) Pitch
(B) Back pitch
(C) Diagonal pitch
(D) Diametric pitch
Answer: C
97. In the below figure, the stress corresponding to point ‘D’ is
(A) Yield point stress
(B) Breaking stress
(C) Ultimate stress
(D) Elastic limit
Answer: C
98. A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The maximum shear stress will be
(A) -100 MPa
(B) 250 MPa
(C) 300 MPa
(D) 400 MPa
Answer: B
99. A cylindrical section having no joint is known as
(A) Joint less section
(B) Homogeneous section
(C) Perfect section
(D) Seamless section
Answer: D
100. A beam which is fixed at one end and free at the other is called
(A) Simply supported beam
(B) Fixed beam
(C) Overhanging beam
(D) Cantilever beam
Answer: D
101. The neutral axis of a transverse section of a beam passes through the centre of gravity of the section and is
(A) In the vertical plane
(B) In the horizontal plane
(C) In the same plane in which the beam bends
(D) At right angle to the plane in which the beam bends
Answer: D
102. The value of Poisson’s ratio for steel is between
(A) 0.01 to 0.1
(B) 0.23 to 0.27
(C) 0.25 to 0.33
(D) 0.4 to 0.6
Answer: C
103. The columns whose slenderness ratio is less than 80, are known as
(A) Short columns
(B) Long columns
(C) Weak columns
(D) Medium columns
Answer: A
104. The stress developed in a material at breaking point in extension is called
(A) Breaking stress
(B) Fracture stress
(C) Yield point stress
(D) Ultimate tensile stress
Answer: A
105. For riveting, the size of hole drilled in plates is __________ shank diameter of rivet.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: C
106. Proof resilience per material is known as
(A) Resilience
(B) Proof resilience
(C) Modulus of resilience
(D) Toughness
Answer: C
107. The capacity of a strained body for doing work on the removal of the straining force, is called
(A) Strain energy
(B) Resilience
(C) Proof resilience
(D) Impact energy
Answer: B
108. In a tensile test on mild steel specimen, the breaking stress as compared to ultimate tensile stress is
(A) More
(B) Less
(C) Same
(D) More/less depending on composition
Answer: B
109. A column of length (l) with both ends fixed may be considered as equivalent to a column of length __________ with both ends hinged.
(A) l/8
(B) l/4
(C) l/2
(D) l
Answer: C
110. If the depth is kept constant for a beam of uniform strength, then its width will vary in proportional to
(A) Bending moment (i.e. M)
(B) Bending moment² (i.e. M²)
(C) Bending moment³ (i.e. M³)
(D) Bending moment⁴ (i.e. M⁴)
Answer: A
111. In a tensile test, near the elastic limit zone, the
(A) Tensile strain increases more quickly
(B) Tensile strain decreases more quickly
(C) Tensile strain increases in proportion to the stress
(D) Tensile strain decreases in proportion to the stress
Answer: A
112. The pull required to crush the rivet per pitch length is
(A) p.t.σt
(B) d.t.σc
(C) π/4 × d² × σt
(D) π/4 × d² × σc
Answer: B
113. The total strain energy stored in a body is termed as
(A) Resilience
(B) Proof resilience
(C) Modulus of resilience
(D) Toughness
Answer: A
114. The extension of a circular bar tapering uniformly from diameter d₁ at one end to diameter d₂ at the other end and subjected to an axial pull of ‘P’ is given by
(A) δl = 4PE/ πl²
(B) δl = 4πld²/PE
(C) δl = 4Pl/πEd₁d₂
(D) δl = 4PlE/ πd₁d₂
Answer: C
115. The maximum bending moment for the beam shown in the below figure, is
(A) wl²/3√3
(B) wl²/6√3
(C) wl²/9√3
(D) wl²/12√3
Answer: C
116. Efficiency of a riveted joint is the ratio of its strength (max. load it can resist without failure) to the strength of the unpunched plate in
(A) Tension
(B) Compression
(C) Bearing
(D) Any one of the above
Answer: A
117. The pull required to tear off the plate per pitch length is (where p = Pitch of rivets, t = Thickness of plates, and σt, τ and σc = Permissible tensile, shearing and crushing stresses respectively)
(A) (p – 2d) t × σc
(B) (p – d) t × τ
(C) (p – d) t × σt
(D) (2p – d) t × σt
Answer: C
118. In a belt drive, the pulley diameter is doubled, the belt tension and pulley width remaining same. The changes required in key will be
(A) Increase key length
(B) Increase key depth
(C) Increase key width
(D) Double all the dimensions
Answer: C
119. In the below figure, curve D represents_________.
(A) Mild steel
(B) Cast iron
(C) Concrete
(D) Bone of these
Answer: A
120. The bending moment of a cantilever beam of length ‘l’ and carrying a uniformly distributed load of ‘w’ per unit length is __________ at the fixed end.
(A) wl/4
(B) wl/2
(C) wl
(D) wl²/2
Answer: D
121. Young’s modulus is defined as the ratio of
(A) Volumetric stress and volumetric strain
(B) Lateral stress and lateral strain
(C) Longitudinal stress and longitudinal strain
(D) Shear stress to shear strain
Answer: C
122. The layer at the center of gravity of the beam as shown in the below figure, will be
(A) In tension
(B) In compression
(C) Neither in tension nor in compression
(D) None of these
Answer: C
123. When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the minimum normal stress is
(A) (σx/2) + (1/2) × √(σx² + 4 τ²xy)
(B) (σx/2) – (1/2) × √(σx² + 4 τ²xy)
(C) (σx/2) + (1/2) × √(σx² – 4 τ²xy)
(D) (1/2) × √(σx² + 4 τ²xy)
Answer: B
124. Tensile strength of a material is obtained by dividing the maximum load during the test by the
(A) Area at the time of fracture
(B) Original cross-sectional area
(C) Average of (A) and (B)
(D) Minimum area after fracture
Answer: B
125. The section modulus of a circular section about an axis through its C.G., is
(A) πd²/4
(B) πd²/16
(C) πd3/16
(D) πd3/32
Answer: D
126. If a part is constrained to move and heated, it will develop
(A) Principal stress
(B) Tensile stress
(C) Compressive stress
(D) Shear stress
Answer: C
127. The moment of resistance of a balanced reinforced concrete beam is based on the stresses in
(A) Steel only
(B) Concrete only
(C) Steel and concrete both
(D) None of these
Answer: C
128. The property of a material by virtue of which it can be beaten or rolled into plates is called
(A) Malleability
(B) Ductility
(C) Plasticity
(D) Elasticity
Answer: A
129. In case of an under-reinforced beam, the depth of actual neutral axis is __________ that of the critical neutral axis.
(A) Same as
(B) Less than
(C) Greater than
(D) None of these
Answer: B
130. The energy absorbed in a body, when it is strained within the elastic limits, is known as
(A) Strain energy
(B) Resilience
(C) Proof resilience
(D) Modulus of resilience
Answer: A
131. A simply supported beam with a gradually varying load from zero at ‘B’ and ‘w’ per unit length at ‘A’ is shown in the below figure. The shear force at ‘B’ is equal to
(A) wl/6
(B) wl/3
(C) wl
(D) 2wl/3
Answer: A 1
132. A fletched beam is used to
(A) Change the shape of the beam
(B) Effect the saving in material
(C) Equalize the strength in tension and compression
(D) Increase the cross-section of the beam
Answer: C
133. Percentage reduction in area performing tensile test on cast iron may be of the order of
(A) 50%
(B) 25%
(C) 20%
(D) 30%
Answer: C
134. A beam is loaded as cantilever. If the load at the end is increased, the failure will occur
(A) In the middle
(B) At the tip below the load
(C) At the support
(D) Anywhere
Answer: D
135. The assumption made in Euler’s column theory is that
(A) The failure of column occurs due to buckling alone
(B) The length of column is very large as compared to its cross-sectional dimensions
(C) The column material obeys Hooke’s law
(D) All of the above
Answer: D
136. If the rivets in adjacent rows are staggered and the outermost row has only one rivets, the arrangement of the rivets is called
(A) Chain riveting
(B) Zigzag riveting
(C) Diamond riveting
(D) Crisscross riveting
Answer: C
137. The point of contraflexure is a point where
(A) Shear force changes sign
(B) Bending moment changes sign
(C) Shear force is maximum
(D) Bending moment is maximum
Answer: B
138. The value of shear stress which is induced in the shaft due to the applied couple varies
(A) From maximum at the center to zero at the circumference
(B) From zero at the center to maximum at the circumference
(C) From maximum at the center to minimum at the circumference
(D) From minimum at the center to maximum at the circumference
Answer: B
139. The extremities of any diameter on Mohr’s circle represent
(A) Principal stresses
(B) Normal stresses on planes at 45°
(C) Shear stresses on planes at 45°
(D) Normal and shear stresses on a plane
Answer: B
140. The materials having same elastic properties in all directions are called
(A) Ideal materials
(B) Uniform materials
(C) Isotropic materials
(D) Piratical materials
Answer: C
141. The ratio of the largest load in a test to the original cross-sectional area of the test piece is called
(A) Elastic limit
(B) Yield stress
(C) Ultimate stress
(D) Breaking stress
Answer: C
142. A column is said to be a short column, when
(A) Its length is very small
(B) Its cross-sectional area is small
(C) The ratio of its length to the least radius of gyration is less than 80
(D) The ratio of its length to the least radius of gyration is more than 80
Answer: C
143. The total elongation produced in a bar of uniform section hanging vertically downwards due to its own weight is equal to that produced by a weight
(A) Of same magnitude as that of bar and applied at the lower end
(B) Half the weight of bar applied at lower end
(C) Half of the square of weight of bar applied at lower end
(D) One fourth of weight of bar applied at lower end
Answer: B
144. The lower layer of the beam as shown in the below figure, will be
(A) In tension
(B) In compression
(C) Neither in tension nor in compression
(D) None of these
Answer: A
145. The tensile strength of the welded joint for double fillet is (where s = Leg or size of the weld, l = Length of weld, and σt = Allowable tensile stress for weld metal)
(A) 0.5 s.l.σt
(B) s.l.σt
(C) √2 s.l.σt
(D) 2.s.l.σt
Answer: C
146. If a material expands freely due to heating it will develop
(A) Thermal stresses
(B) Tensile stress
(C) Bending
(D) No stress
Answer: D
147. When a body is subjected to biaxial stress i.e. direct stresses (σx) and (σy) in two mutually perpendicular planes accompanied by a simple shear stress (τxy), then maximum normal stress is
(A) (σx + σy)/2 + (1/2) × √[(σx – σy)² + 4 τ²xy]
(B) (σx + σy)/2 – (1/2) × √[(σx – σy)² + 4 τ²xy]
(C) (σx – σy)/2 + (1/2) × √[(σx + σy)² + 4 τ²xy]
(D) (σx – σy)/2 – (1/2) × √[(σx + σy)² + 4 τ²xy]
Answer: A
148. The stress at which extension of the material takes place more quickly as compared to the increase in load is called
(A) Elastic point of the material
(B) Plastic point of the material
(C) Breaking point of the material
(D) Yielding point of the material
Answer: D
149. A cantilever beam is one which is
(A) Fixed at both ends
(B) Fixed at one end and free at the other end
(C) Supported at its ends
(D) Supported on more than two supports
Answer: B
150. In a prismatic member made of two materials so joined that they deform equally under axial stress, the unit stresses in two materials are
(A) Equal
(B) Proportional to their respective moduli of elasticity
(C) Inversely proportional to their moduli of elasticity
(D) Average of the sum of moduli of elasticity
Answer: B
151. A circular shaft fixed at, A has diameter D for half of its length and diameter D/2 over the other half, as shown in the below figure. If the rotation of B relative to A is 0.1 radian, the rotation of C relative to B will be
(A) 0.4 radian
(B) 0.8 radian
(C) 1.6 radian
(D) 3.2 radian
Answer: C
152. The shear force diagram of a cantilever beam of length ‘l’ and carrying a uniformly distributed load of w per unit length will be
(A) A right angled triangle
(B) An isosceles triangle
(C) An equilateral triangle
(D) A rectangle
Answer: A
153. The safe twisting moment for a compound shaft is equal to the
(A) Maximum calculated value
(B) Minimum calculated value
(C) Mean value
(D) Extreme value
Answer: B
154. When a bar is subjected to a change of temperature and its deformation is prevented, the stress induced in the bar is
(A) Tensile stress
(B) Compressive stress
(C) Shear stress
(D) Thermal stress
Answer: D
155. A thin mild steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under
(A) Uniform throughout
(B) Increase uniformly
(C) First increase and then decrease
(D) Increase uniformly first and then increase rapidly
157. Which is the false statement about true stress strain method?
(A) It does not exist
(B) It is more sensitive to changes in both metallurgical and mechanical conditions
(C) It gives a more accurate picture of the ductility
(D) It can be correlated with stress strain values in other tests like torsion, impact, combined stress tests etc.
Answer: A
158. The bending equation is
(A) M/I = σ/y = E/R
(B) T/J = τ/R = Cθ/l
(C) M/R = T/J = Cθ/l
(D) T/l= τ/J = R/Cθ
Answer: A
159. For which material the Poisson’s ratio is more than unity
(A) Steel
(B) Copper
(C) Aluminium
(D) None of the above
Answer: D
160. When a body is subjected to a direct tensile stress (σ) in one plane, then maximum normal stress occurs at a section inclined at _________ to the normal of the section.
(A) 0°
(B) 30°
(C) 45°
(D) 90°
Answer: A
161. Flow stress corresponds to
(A) Fluids in motion
(B) Breaking point
(C) Plastic deformation of solids
(D) Rupture stress
Answer: C
162. The thickness of a thin cylindrical shell with hemispherical ends is _________ that of spherical ends.
(A) Equal to
(B) More than
(C) Less than
(D) None of these
Answer: B
163. A riveted joint in which every rivet of a row is opposite to other rivet of the outer row, is known as
(A) Chain riveted joint
(B) Diamond riveted joint
(C) Crisscross riveted joint
(D) Zigzag riveted joint
Answer: A
164. The maximum tangential stress in a thick cylindrical shell is always _________ the internal pressure acting on the shell.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: C
165. If percentage reduction in area of a certain specimen made of material ‘A’ under tensile test is 60% and the percentage reduction in area of a specimen with same dimensions made of material ‘B’ is 40%, then
(A) The material A is more ductile than material B
(B) The material B is more ductile than material A
(C) The ductility of material A and B is equal
(D) The material A is brittle and material B is ductile
Answer: A
166. Which of the following materials is most elastic?
(A) Rubber
(B) Plastic
(C) Brass
(D) Steel
Answer: D
167. Strain is equal to (where l = Original length, and δl = Change in length)
(A) l/δl
(B) δl/l
(C) l.δl
(D) l + δl
Answer: B
168. The ratio of direct stress to volumetric strain in case of a body subjected to three mutually perpendicular stresses of equal intensity, is equal to
(A) Young’s modulus
(B) Bulk modulus
(C) Modulus of rigidity
(D) Modulus of elasticity
Answer: B
169. Which of the following statement is wrong?
(A) The deformation of the bar per unit length in the direction of the force is called linear strain.
(B) The Poisson’s ratio is the ratio of lateral strain to the linear strain.
(C) The ratio of change in volume to the original volume is called volumetric strain.
(D) The bulk modulus is the ratio of linear stress to the linear strain.
Answer: D
170. Diamond riveted joint can be adopted in the case of following type of joint
(A) Butt joint
(B) Lap joint
(C) Double riveted lap joints
(D) All types of joints
Answer: A
171. When a body is subjected to biaxial stress i.e. direct stresses (σx) and (σy) in two mutually perpendicular planes accompanied by a simple shear stress (τxy), then minimum normal stress is
(A) (σx + σy)/2 + (1/2) × √[(σx – σy)² + 4 τ²xy]
(B) (σx + σy)/2 – (1/2) × √[(σx – σy)² + 4 τ²xy]
(C) (σx – σy)/2 + (1/2) × √[(σx + σy)² + 4 τ²xy]
(D) (σx – σy)/2 – (1/2) × √[(σx + σy)² + 4 τ²xy]
Answer: B
172. The unit of Young’s modulus is
(A) mm/mm
(B) kg/cm
(C) Kg
(D) kg/cm²
Answer: D
173. When a body is subjected to three mutually perpendicular stresses, of equal intensity, the ratio of direct stress to the corresponding volumetric strain is known as
(A) Young’s modulus
(B) Modulus of rigidity
(C) Bulk modulus
(D) Poisson’s ratio
Answer: C
174. The value of modulus of elasticity for mild steel is of the order of
(A) 2.1 × 10⁵ kg/cm²
(B) 2.1 × 10⁶ kg/cm²
(C) 2.1 × 10⁷ kg/cm²
(D) 0.1 × 10⁶ kg/cm²
Answer: B
175. A pressure vessel is said to be a thick shell, when
(A) It is made of thick sheets
(B) The internal pressure is very high
(C) The ratio of wall thickness of the vessel to its diameter is less than 1/10.
(D) The ratio of wall thickness of the vessel to its diameter is greater than 1/10.
Answer: D
176. The strain energy stored in a body due to suddenly applied load compared to when it is applied gradually is
(A) Same
(B) Twice
(C) Four times
(D) Eight times
Answer: C
177. The deformation of a bar under its own weight compared to the deformation of same body subjected to a direct load equal to weight of the body is
(A) Same
(B) Double
(C) Half
(D) Four times
Answer: C
178. A continuous beam is one which is
(A) Fixed at both ends
(B) Fixed at one end and free at the other end
(C) Supported on more than two supports
(D) Extending beyond the supports
Answer: C
179. The radius of the Mohr’s circle in the given figure is equal to
Som Question No 14
(A) Sum of two principal stresses
(B) Difference of two principal stresses
(C) Half the sum of two principal stresses
(D) Half the difference of two principal stresses
Answer: D
180. The maximum shear stress, in the given figure, is equal to __________ of the Mohr’s circle.
(A) Radius
(B) Diameter
(C) Circumference
(D) Area
Answer: A
181. A key is subjected to side pressure as well at shearing forces. These pressures are called
(A) Bearing stresses
(B) Fatigue stresses
(C) Crushing stresses
(D) Resultant stresses
Answer: A
182. When a closely-coiled helical spring of mean diameter (D) is subjected to an axial load (W), the stiffness of the spring is given by
(A) Cd⁴/D3n
(B) Cd⁴/2D3n
(C) Cd⁴/4D3n
(D) Cd⁴/8D3n
Answer: D
183. During a tensile test on a specimen of 1 cm cross-section, maximum load observed was 8 tonnes and area of cross-section at neck was 0.5 cm². Ultimate tensile strength of specimen is
(A) 4 tonnes/ cm²
(B) 8 tonnes/ cm²
(C) 16 tonnes/ cm²
(D) 22 tonnes/ cm²
Answer: B
184. When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the maximum shear stress is
(A) (σx/2) + (1/2) × √(σx² + 4 τ²xy)
(B) (σx/2) – (1/2) × √(σx² + 4 τ²xy)
(C) (σx/2) + (1/2) × √(σx² – 4 τ²xy)
(D) (1/2) × √(σx² + 4 τ²xy)
Answer: D
185. The change in the unit volume of a material under tension with increase in its Poisson’s ratio will
(A) Increase
(B) Decrease
(C) Remain same
(D) Increase initially and then decrease
Answer: B
186. A material capable of absorbing large amount of energy before fracture is known as
(A) Ductility
(B) Toughness
(C) Resilience
(D) Shock proof
Answer: B
187. The shear force at the ends of a simply supported beam carrying a uniformly distributed load of w per unit length is
(A) Zero at its both ends
(B) wl at one end and -wl at the other end
(C) wl/2 at one end and -wl/ 2 at the other end
(D) wl²/2 at one end and -wl²/ 2 at the other end
Answer: C
188. Deformation per unit length in the direction of force is known as
(A) Strain
(B) Lateral strain
(C) Linear strain
(D) Linear stress
Answer: C
189. Which of the following statement is correct?
(A) The energy stored in a body, when strained within elastic limit is known as strain energy.
(B) The maximum strain energy which can be stored in a body is termed as proof resilience.
(C) The proof resilience per unit volume of a material is known as modulus of resilience.
(D) All of the above
Answer: D
190. Rupture stress is
(A) Breaking stress
(B) Maximum load/original cross-sectional area
(C) Load at breaking point/Area
(D) Load at breaking point/neck area
Answer: D
191. When two shafts of same length, one of which is hollow, transmit equal torques and have equal maximum stress, then they should have equal
(A) Polar moment of inertia
(B) Polar modulus
(C) Diameter
(D) Angle of twist
Answer: B
192. Longitudinal stress in a thin cylinder is
(A) Equal to the hoop stress
(B) Twice the hoop stress
(C) Half of the hoop stress
(D) One fourth of hoop stress
Answer: C
193. A beam of uniform strength may be obtained by
(A) Keeping the width uniform and varying the depth
(B) Keeping the depth uniform and varying the width
(C) Varying the width and depth both
(D) Any one of the above
Answer: D
194. Which of the following has no unit?
(A) Kinematic viscosity
(B) Surface tension
(C) Bulk modulus
(D) Strain
Answer: D
195. The deformation of the bar per unit length in the direction of the force is known as
(A) Linear strain
(B) Lateral strain
(C) Volumetric strain
(D) Shear strain
Answer: A
196. In the below figure, __________ represents glass.
(A) Curve A
(B) Curve B
(C) Curve C
(D) Curve D
Answer: C
197. Hook’s law holds good up to
(A) Yield point
(B) Elastic limit
(C) Plastic limit
(D) Breaking point
Answer: B
198. A thin spherical shell of diameter (d) and thickness (t) is subjected to an internal pressure (p). The stress in the shell material is
(A) pd/t
(B) pd/2t
(C) pd/4t
(D) pd/8t
Answer: C
199. Poisson’s ratio is defined as the ratio of
(A) Longitudinal stress and longitudinal strain
(B) Longitudinal stress and lateral stress
(C) Lateral stress and longitudinal stress
(D) Lateral stress and lateral strain
Answer: C
200. The rectangular beam ‘A’ has length l, width b and depth d. Another beam ‘B’ has the same length and width but depth is double that of ‘A’. The elastic strength of beam B will be __________ as compared to beam A.
(A) Same
(B) Double
(C) Four times
(D) Six times
Answer: C
201. The value of Poisson’s ratio for cast iron is
(A) 0.1 to 0.2
(B) 0.23 to 0.27
(C) 0.25 to 0.33
(D) 0.4 to 0.6
Answer: B
202. According to Euler’s column theory, the crippling load of a column is given by p = π²EI/Cl². In the Euler’s formula, the value of C for a column with one end fixed and the other end free, is
(A) 1/2
(B) 1
(C) 2
(D) 4
Answer: D
203. The elasticity of various materials is controlled by its
(A) Ultimate tensile stress
(B) Proof stress
(C) Stress at yield point
(D) Stress at elastic limit
Answer: D
204. A simply supported beam of length ‘l’ carries a point load ‘W’ at a point C as shown in the below figure. The maximum deflection lies at
(A) Point A
(B) Point B
(C) Point C
(D) Between points B and C
Answer: D
205. The shear force diagram for a cantilever beam of length l and carrying a gradually varying load from zero at free end and w per unit length at the fixed end is a
(A) Horizontal straight line
(B) Vertical straight line
(C) Inclined line
(D) Parabolic curve
Answer: D
206. The maximum shear stress in a thin cylindrical shell subjected to internal pressure ‘p’ is
(A) pd/t
(B) pd/2t
(C) pd/4t
(D) pd/8t
Answer: D
207. When a beam is subjected to bending moment, the stress at any point is __________ the distance of the point from the neutral axis.
(A) Equal to
(B) Directly proportional to
(C) Inversely proportional to
(D) Independent of
Answer: B
208. In a tensile test, when the material is stressed beyond elastic limit, the tensile strain __________ as compared to the stress.
(A) Decreases slowly
(B) Increases slowly
(C) Decreases more quickly
(D) Increases more quickly
Answer: D
209. A fixed beam is one which is fixed at _________.
(A) One of its ends
(B) Both of its ends
(C) The middle
(D) None of these
Answer: B
210. If the modulus of elasticity for a given material is twice its modulus of rigidity, then bulk modulus is equal to
(A) 2C
(B) 3C
(C) 2C/3
(D) 3C/2
Answer: C
211. When a load on the free end of a cantilever beam is increased, failure will occur
(A) At the free end
(B) At the fixed end
(C) In the middle of the beam
(D) At a distance 2l/3 from free end
Answer: B
212. The rectangular beam ‘A ‘ has length l, width b and depth d. Another beam ‘B’ has the same width and depth but length is double that of ‘A’. The elastic strength of beam ‘B’ will be __________ as compared to beam A.
(A) Same
(B) One-half
(C) One-fourth
(D) One-eighth
Answer: B
213. In leaf springs, the maximum bending stress developed in the plates is (where W = Load acting on the spring, l = Span of the spring, n = Number of plates, b = Width of plates, and t = Thickness of plates)
(A) Wl/nbt²
(B) 3Wl/2nbt²
(C) 2Wl/nbt²
(D) 3Wl/nbt²
Answer: B
214. The extension of a circular bar tapering uniformly from diameter d₁ at one end to diameter d₂ at the other end, and subjected to an axial pull of P is _________ the extension of a circular bar of diameter d₁ d₂ subjected to the same load P.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: A
215. In a thick cylindrical shell subjected to an internal pressure (p), the radial stress across the thickness of the cylinder is
(A) Maximum at the outer surface and minimum at the inner surface
(B) Maximum at the inner surface and minimum at the outer surface
(C) Maximum at the outer surface and zero at the inner surface
(D) Maximum at the inner surface arid zero at the outer surface
Answer: D
216. A column with maximum equivalent length has
(A) Both ends hinged
(B) Both ends fixed
(C) One end fixed and the other end hinged
(D) One end fixed and the other end free
Answer: D
217. The ratio of change in volume to the original volume is called
(A) Linear strain
(B) Lateral strain
(C) Volumetric strain
(D) Poisson’s ratio
Answer: C
218. Which of the following statement is wrong?
(A) In the theory of simple bending, the assumption is that the plane sections before bending remains plane after bending.
(B) In a beam subjected to bending moment, the strain is directly proportional to the distance from the neutral axis.
(C) At the neutral axis of a beam, the bending stress is maximum.
(D) The bending stress in a beam is inversely proportional to the section modulus.
Answer: C
219. The polar moment of inertia of a solid circular shaft of diameter (D) is
(A) πD³/16
(B) πD³/32
(C) πD⁴/32
(D) πD⁴/64
Answer: C
220. In Mohr’s circle, the center of circle from Y-axis is taken as
(A) (σx – σy)/2
(B) (σx + σy)/2
(C) [(σx – σy)/2] + τ
(D) [(σx + σy)/2] + τ
Answer: B
221. Shear strength of the welded joint for double parallel fillet is (where τ = Allowable shear stress for weld metal)
(A) 0.5 s.l.τ
(B) s.l.τ
(C) √2 s.l.τ
(D) 2.s.l.τ
Answer: C
222. When a shaft, is subjected to torsion, the shear stress induced in the shaft varies from
(A) Minimum at the center to maximum at the circumference
(B) Maximum at the center to minimum at the circumference
(C) Zero at the center to maximum at the circumference
(D) Maximum at the center to zero at the circumference
Answer: C
223. The strain energy stored in a body, when the load is gradually applied, is (where σ = Stress in the material of the body, V = Volume of the body, and E = Modulus of elasticity of the material)
(A) σE/V
(B) σV/E
(C) σ²E/2V
(D) σ²V/2E
Answer: D
224. At the neutral axis of a beam, the shear stress is
(A) Zero
(B) Minimum
(C) Maximum
(D) Infinity
Answer: C
225. In a stress-strain diagram for mild steel, as shown in the below figure, the point ‘A’ represents
(A) Elastic limit
(B) Upper yield point
(C) Lower yield point
(D) Breaking point
Answer: A
226. When a body is subjected to two equal and opposite forces, acting tangentially across the resisting section, as a result of which the body tends to shear off across the section, the stress and strain induced is
(A) Tensile stress, tensile strain
(B) Compressive stress, compressive strain
(C) Shear stress, tensile strain
(D) Shear stress, shear strain
Answer: D
227. The given figure shows the Mohr’s circle of stress for two unequal and like principal stresses (σx and σy) acting at a body across two mutually perpendicular planes. The tangential stress is given by
(A) OC
(B) OP
(C) OQ
(D) PQ
Answer: D
228. The strain energy stored in a hollow circular shaft of outer diameter (D) and inner diameter (d) subjected to shear stress is
(A) (τ²/2C) (D² – d²/D) × Volume of shaft
(B) (τ²/2C) (D² + d²/D) × Volume of shaft
(C) (τ²/4C) (D² – d²/D) × Volume of shaft
(D) (τ²/4C) (D² + d²/D) × Volume of shaft
Answer: D
229. The center to center distance, between two consecutive rivets in a row, is called
(A) Margin
(B) Pitch
(C) Back pitch
(D) Diagonal pitch
Answer: B
230. Two shafts ‘A’ and ‘B’ are made of same material. The shaft ‘A’ is of diameter D and shaft ‘B’ is of diameter D/2. The strength of shaft ‘B’ is _________ as that of shaft ‘A’
(A) One-eighth
(B) One-fourth
(C) One-half
(D) Four times
Answer: A
231. According to Unwin’s formula, the relation between diameter of rivet hole (d) and thickness of plate (t) is given by (where d and t are in mm)
(A) d = t
(B) d = 1.6 t
(C) d = 2t
(D) d = 6t
Answer: D
232. A tensile test is performed on a round bar. After fracture, it has been found that the diameter remains approximately same at fracture. The material under test was
(A) Mild steel
(B) Cast iron
(C) Glass
(D) Copper
Answer: B
233. A rectangular beam of length l supported at its two ends carries a central point load W. The maximum deflection occurs
(A) At the ends
(B) At l/3 from both ends
(C) At the center
(D) None of these
Answer: C
234. The ratio of the lateral strain to the linear strain is called
(A) Modulus of elasticity
(B) Modulus of rigidity
(C) Bulk modulus
(D) Poisson’s ratio
Answer: D
235. The shear force of a cantilever beam of length l carrying a uniformly distributed load of w per unit length is _________ at the free end.
(A) Zero
(B) wl/4
(C) wl/2
(D) wl
Answer: A
236. In a simple bending of beams, the stress in the beam varies
(A) Linearly
(B) Parabolically
(C) Hyperbolically
(D) Elliptically
Answer: A
237. The shear force at a point on a beam is the algebraic __________ of all the forces on either side of the point.
(A) Sum
(B) Difference
(C) Multiplication
(D) Division
Answer: A
238. When a cantilever beam is loaded at its free end, the maximum compressive stress shall develop at
(A) Bottom fibre
(B) Top fibre
(C) Neutral axis
(D) Center of gravity
Answer: A
239. The total strain energy stored in a body is termed as
(A) Resilience
(B) Proof resilience
(C) Impact energy
(D) Modulus of resilience
Answer: A
240. When a body is subjected to biaxial stress i.e. direct stresses (σx) and (σy) in two mutually perpendicular planes accompanied by a simple shear stress (τxy), then maximum shear stress is
(A) (1/2) × √[(σx – σy)² + 4 τ²xy]
(B) (1/2) × √[(σx + σy)² + 4 τ²xy]
(C) √[(σx – σy)² + τ²xy]
(D) √[(σx + σy)² + τ²xy]
Answer: A
241. According to Euler’s column theory, the crippling load for a column length (l) hinged at both ends, is
(A) π²EI/l²
(B) π²EI/4l²
(C) 4π²EI/l²
(D) 2π²EI/l²
Answer: A
242. A thin cylindrical shell of diameter (d), length (l) and thickness (t) is subjected to an internal pressure (p). The ratio of longitudinal strain to hoop strain is
(A) (m – 2)/(2m – 1)
(B) (2m – 1)/(m – 2)
(C) (m – 2)/(2m + 1)
(D) (2m + 1)/(m – 2)
Answer: A
243. Young’s modulus may be defined as the ratio of
(A) Linear stress to lateral strain
(B) Lateral strain to linear strain
(C) Linear stress to linear strain
(D) Shear stress to shear strain
Answer: C
244. The maximum bending moment for the beam shown in the below figure, lies at a distance of ________ from the end B.
(A) l/2
(B) l/3
(C) l/√2
(D) l/√3
Answer: D
245. Two closely-coiled helical springs ‘A’ and ‘B’ are equal in all respects but the number of turns of spring ‘A’ is double that of spring ‘B’. The stiffness of spring ‘A’ will be __________ that of spring ‘B’.
(A) One-sixteenth
(B) One-eighth
(C) One-fourth
(D) One-half
Answer: D
246. The bending moment on a section is maximum where shear force is
(A) Minimum
(B) Maximum
(C) Changing sign
(D) Zero
Answer: C
247. The stress developed in the material without any permanent set is called
(A) Elastic limit
(B) Yield stress
(C) Ultimate stress
(D) Breaking stress
Answer: A
248. Two closely coiled helical springs ‘A’ and ‘B’ are equal in all respects but the diameter of wire of spring ‘A’ is double that of spring ‘B’ The stiffness of spring ‘B’ will be __________ that of spring ‘A’
(A) One-sixteenth
(B) One-eighth
(C) One-fourth
(D) One-half
Answer: A
249. In a riveted joint, when the number of rivets decreases from the inner most row to outer most row, the joint is said to be
(A) Chain riveted
(B) Zig-zag riveted
(C) Diamond riveted
(D) None of these
Answer: C
250. The polar modulus for a hollow shaft of outer diameter (D) and inner diameter (d) is
(A) (π/4) × (D² – d²)/D
(B) (π/16) × (D3 – d3)/D
(C) (π/16) × (D⁴ – d⁴)/D
(D) (π/32) × (D⁴ – d⁴)/D
Answer: C
251. A leaf spring is supported at the
(A) Ends and loaded at the center
(B) Center and loaded at the ends
(C) Ends and loaded anywhere
(D) Center and loaded anywhere
Answer: B
252. The assumption made in the theory of the reinforced cement concrete beam is that
(A) All the tensile stresses are taken up by the steel reinforcement only
(B) There is a sufficient bond between steel and concrete
(C) The steel and concrete are stressed within its elastic limit
(D) All of the above
Answer: D
253. The ultimate tensile stress for mild steel is __________ the ultimate compressive stress.
(A) Equal to
(B) Less than
(C) More than
(D) None of these
Answer: C
254. The neutral axis of the cross-section of a beam is that axis at which the bending stress is
(A) Zero
(B) Minimum
(C) Maximum
(D) Infinity
Answer: A
255. When a thin cylindrical shell is subjected to an internal pressure, there will be
(A) A decrease in diameter and length of the shell
(B) An increase in diameter and decrease in length of the shell
(C) A decrease in diameter and increase in length of the shell
(D) An increase in diameter and length of the shell
Answer: D
256. When the shear force diagram is a parabolic curve between two points, it indicates that there is a
(A) Point load at the two points
(B) No loading between the two points
(C) Uniformly distributed load between the two points
(D) Uniformly varying load between the two points
Answer: D
257. In order to avoid sliding of masonry dam, the force of friction between the dam and soil should be at least __________ the total water pressure per meter length.
(A) Equal to
(B) 1.5 times
(C) Double
(D) 2.5 times
Answer: B
258. The design of thin cylindrical shells is based on
(A) Hoop stress
(B) Longitudinal stress
(C) Arithmetic mean of the hoop and the longitudinal stress
(D) Geometric mean of the hoop and longitudinal stress
Answer: A
259. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The minimum normal stress will be
(A) 400 MPa
(B) 500 MPa
(C) 900 MPa
(D) 1400 MPa
Answer: A
260. In the below figure, the point C represents
(A) Elastic limit
(B) Upper yield point
(C) Lower yield point
(D) Breaking point
Answer: C
261. If the section modulus of a beam is increased, the bending stress in the beam will
(A) Not change
(B) Increase
(C) Decrease
(D) None of these
Answer: C
262. In the below figure, the point E represents.
(A) The maximum stress
(B) The minimum stress
(C) No stress
(D) None of these
Answer: A
263. The maximum deflection of a cantilever beam of length ‘l’ with a point load ‘W’ at the free end is
(A) Wl3/3EI
(B) Wl3/8EI
(C) Wl3/16EI
(D) Wl3/48EI
Answer: A
264. The strength of a riveted joint is equal to the
(A) Pull required to tear off the plate per pitch length (Pt)
(B) Pull required to shear off the rivet per pitch length (Ps)
(C) Pull required to crush the rivet per pitch length (Pc)
(D) Minimum value of Pt, Ps or Pc
Answer: D
265. The torsional rigidity of a shaft is given by
(A) T/J
(B) T/θ
(C) T/r
(D) T/G
Answer: B
266. A localized compressive stress at the area of contact between two members is known as
(A) Tensile stress
(B) Bending stress
(C) Crushing stress
(D) Shear stress
Answer: C
267. The product of Young’s modulus (E) and moment of inertia (I) is known as
(A) Modulus of rigidity
(B) Bulk modulus
(C) Flexural rigidity
(D) Torsional rigidity
Answer: C
268. A body is subjected to a direct tensile stress (σ) in one plane. The shear stress is maximum at a section inclined at __________ to the normal of the section.
(A) 45° and 90°
(B) 45° and 135°
(C) 60° and 150°
(D) 30° and 135°
Answer: B
269. Two solid shafts ‘A’ and ‘B’ are made of the same material. The shaft ‘A’ is of 50 mm diameter and shaft ‘B’ is of 100 mm diameter. The strength of shaft ‘B’ is _________ as that of shaft A.
(A) One-half
(B) Double
(C) Four times
(D) Eight times
Answer: D
270. For a given stress, the ratio of moment of resistance of a beam of square cross-section when placed with its two sides horizontal to the moment of resistance with its diagonal horizontal, is
(A) 1/2
(B) 1
(C) 1/√2
(D) √2
Answer: D
271. The ductility of the material __________ with the decrease in percentage elongation of a specimen under tensile test.
(A) Increases
(B) Decreases
(C) Remain same
(D) None of these
Answer: B
272. The length of a conical bar is l, diameter of base is d and weight per unit volume is w. It is fixes at its upper end and hanging freely. The elongation of the bar under the action of its own weight will be
(A) wl²/2E
(B) wl²/4E
(C) wl²/6E
(D) wl²/8E
Answer: C
273. The ratio of linear stress to the linear strain is called
(A) Modulus of rigidity
(B) Modulus of elasticity
(C) Bulk modulus
(D) Poisson’s ratio
Answer: B
274. For no tension condition in the base of a short column of circular section, the line of action of the load should be within a circle of diameter equal to __________ of the main circle.
(A) One-half
(B) One-third
(C) One-fourth
(D) One-eighth
Answer: C
275. The shear modulus of most materials with respect to the modulus of elasticity is
(A) Equal to half
(B) Less than half
(C) More than half
(D) None of these
Answer: B
276. Whenever a material is loaded within elastic limit, stress is __________ strain.
(A) Equal to
(B) Directly proportional to
(C) Inversely proportional to
(D) None of these
Answer: B
277. In the below figure, Hook’s law holds good, for the portion from_________.
(A) O to A
(B) B to D
(C) D to E
(D) None of these
278. The point of contraflexure occurs in
(A) Cantilever beams
(B) Simply supported beams
(C) Overhanging beams
(D) Fixed beams
Answer: C
279. The bending moment of a cantilever beam of length l and carrying a gradually varying load from zero at free end and w per unit length at the fixed end is ________ at the fixed end.
(A) wl/2
(B) wl
(C) wl²/2
(D) wl²/6
Answer: D
280. The maximum deflection of a cantilever beam of length ‘l’ with a uniformly distributed load of ‘w’ per unit length is (where W = wl)
(A) Wl³/3EI
(B) Wl³/8EI
(C) Wl³/16EI
(D) Wl³/48EI
Answer: B
281. When a bar of length l, width b and thickness t is subjected to a pull of P, its
(A) Length, width and thickness increases
(B) Length, width and thickness decreases
(C) Length increases, width and thickness decreases
(D) Length decreases, width and thickness increases
Answer: C
282. A beam of T-section is subjected to a shear force of F. The maximum shear force will occur at the
(A) Top of the section
(B) Bottom of the section
(C) Neutral axis of the section
(D) Junction of web and flange
Answer: C
283. The maximum deflection of a fixed beam of length l carrying a central point load W is
(A) wl³/48 EI
(B) wl³/96 EI
(C) wl³/192 EI
(D) wl³/384 EI
Answer: C
284. The torque transmitted by a hollow shaft of outer diameter (D) and inner diameter (d) is
(A) (π/4) × τ [(D² – d²)/d]
(B) (π/16) × τ [(D³ – d³)/d]
(C) (π/16) × τ [(D⁴ – d⁴)/d]
(D) (π/32) × τ [(D⁴ – d⁴)/d]
Answer: C
285. At the neutral axis of a beam
(A) The layers are subjected to maximum bending stress
(B) The layers are subjected to minimum bending stress
(C) The layers are subjected to compression
(D) The layers do not undergo any strain
Answer: D
286. In a thick cylindrical shell subjected to an internal pressure (p), the tangential stress across the thickness of a cylinder is
(A) Maximum at the outer surface and minimum at the inner surface
(B) Maximum at the inner surface and minimum at the outer surface
(C) Maximum at the outer surface and zero at the inner surface
(D) Maximum at the inner surface and zero at the outer surface
Answer: B
287. When a bar of length l, width b and thickness t is subjected to a push of P, its
(A) Length, width and thickness increases
(B) Length, width and thickness decreases
(C) Length increases, width and thickness decreases
(D) Length decreases, width and thickness increases
Answer: D
288. In a simple bending theory, one of the assumptions is that the plane sections before bending remain plane after bending. This assumption means that
(A) Stress is uniform throughout the beam
(B) Strain is uniform throughout the beam
(C) Stress is proportional to the distance from the neutral axis
(D) Strain is proportional to the distance from the neutral axis
Answer: D
289. For a beam, as shown in the below figure, the maximum deflection lies at
(A) l/3 from B
(B) l/3 from A
(C) √(l² – a²/3) from B
(D) √(l² – b²/3) from A
Answer: C
290. In the above question, the ratio of stiffness of spring ‘B’ to spring ‘A’ will be
(A) 2
(B) 4
(C) 6
(D) 8
Answer: D
291. When a body is subjected to a direct tensile stress (σ) in one plane, then normal stress on an oblique section of the body inclined at an angle ‘θ’ to the normal of the section is
(A) σ cosθ
(B) σ cos²θ
(C) σ sinθ
(D) σ sin²θ
Answer: B
292. The longitudinal stress in a riveted cylindrical shell of diameter (d), thickness (t) and subjected to an internal pressure (p) is
(A) pd/(η × t)
(B) pd/(η × 2t)
(C) pd/(η × 4t)
(D) pd/(η × 8t)
Answer: C
293. Lame’s theory is associated with
(A) Thin cylindrical shells
(B) Thick cylindrical shells
(C) Direct and bending stresses
(D) None of these
Answer: B
294. According to Euler’s column theory, the crippling load of a column is given by p = π² EI/Cl² In this equation, the value of ‘C’ for a column with both ends hinged, is
(A) ¼
(B) ½
(C) 1
(D) 2
Answer: C
295. A riveted joint may fail by
(A) Tearing of the plate at an edge
(B) Tearing of the plate across a row of rivets
(C) Shearing of rivets
(D) Any one of these
Answer: D
296. The tensile strength of ductile materials is _________ its compressive strength.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: C
297. The strain energy stored in a body due to shear stress, is (where τ = Shear stress, C = Shear modulus, and V = Volume of the body)
(A) (τ/2C) × V
(B) 2C/ τV
(C) (τ²/2C) × V
(D) 2C/ τ²V
Answer: C
298. The maximum shear stress is __________ the algebraic difference of maximum and minimum normal stresses.
(A) Equal to
(B) One-fourth
(C) One-half
(D) Twice
Answer: C
299. The object of caulking in a riveted joint is to make the joint
(A) Free from corrosion
(B) Stronger in tension
(C) Free from stresses
(D) Leak proof
Answer: D
300. The Poisson’s ratio for steel varies from
(A) 0.23 to 0.27
(B) 0.27 to 0.30
(C) 0.31 to 0.34
(D) 0.32 to 0.42
Answer: B
301. The shear force of a cantilever beam of length l and carrying a gradually varying load from zero at the free end and w per unit length at the fixed end is _________ at the fixed end.
(A) Zero
(B) wl/4
(C) wl/2
(D) wl
Answer: C
302. The modulus of elasticity for mild steel is approximately equal to
(A) 10 kN/mm²
(B) 80 kN/mm²
(C) 100 kN/mm²
(D) 210 kN/mm²
Answer: D
303. The direct stress induced in a long column is __________ as compared to bending stress.
(A) Same
(B) More
(C) Less
(D) Negligible
Answer: D
304. For a 25 mm hole drilled in plates, the diameter of rivet shank should be
(A) 23 mm
(B) 24.5 mm
(C) 25 mm
(D) 26 mm
Answer: A
305. The elongation of a conical bar under its own weight is __________ that of prismatic bar of the same length.
(A) Equal to
(B) Half
(C) One-third
(D) Two-third
Answer: C
306. A bolt is made to pass through a tube and both of them are tightly fitted with the help of washers and nuts. If the nut is tightened, then
(A) Bolt and tube are under tension
(B) Bolt and tube are under compression
(C) Bolt is under compression and tube is under tension
(D) Bolt is under tension and tube is under compression
Answer: D
307. Two shafts ‘A’ and ‘B’ have the same material. The shaft ‘A’ is solid of diameter 100 mm. The shaft ‘B’ is hollow with outer diameter 100 mm and inner diameter 50 mm. The torque transmitted by shaft ‘B’ is __________ as that of shaft ‘A’.
(A) 1/6
(B) 1/8
(C) 1/4
(D) 15/16
Answer: D
308. Mohr’s circle is used to determine the stresses on an oblique section of a body subjected to
(A) Direct tensile stress in one plane accompanied by a shear stress
(B) Direct tensile stress in two mutually perpendicular directions
(C) Direct tensile stress in two mutually perpendicular directions accompanied by a simple shear stress
(D) All of the above
Answer: D
309. A steel bar 2 m long, 20 mm wide and 10 mm thick is subjected to a pull of 2 kN. If the same bar is subjected to a push of 2 kN, the Poisson’s ratio of the bar in tension will be __________ the Poisson’s ratio for the bar in compression.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: A
310. The assumption, generally, made in the theory of simple bending is that
(A) The beam material is perfectly homogeneous and isotropic
(B) The beam material is stressed within its elastic limit
(C) The plane sections before bending remain plane after bending
(D) All of the above
Answer: D
311. When a body is subjected to two equal and opposite pulls, as a result of which the body tends to extend its length, the stress and strain induced is
(A) Compressive stress, tensile strain
(B) Tensile stress, compressive strain
(C) Tensile stress, tensile strain
(D) Compressive stress, compressive strain
Answer: C
312. The thermal stress in a bar is __________ proportional to the change in temperature.
(A) Directly
(B) Indirectly
(C) Both A and B
(D) None of these
Answer: A
313. A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The minimum normal stress will be
(A) -100 MPa
(B) 250 MPa
(C) 300 MPa
(D) 400 MPa
Answer: A
314. For the beam shown in the below figure, the shear force at A is equal to
(A) wl/6
(B) wl/3
(C) wl
(D) 2wl/3
Answer: B
315. The maximum shear stress developed in a beam of circular section is __________ the average shear stress.
(A) Equal to
(B) 4/3 times
(C) 1.5 times
(D) Twice
Answer: B
316. The bending moment of a cantilever beam of length l and carrying a uniformly distributed load of w per unit length is __________ at the free end.
(A) Zero
(B) wl/4
(C) wl/2
(D) wl
Answer: A
317. For a shaft, the shear stress at a point is __________ the distance from the axis of the shaft.
(A) Equal to
(B) Directly proportional to
(C) Inversely proportional to
(D) None of these
Answer: B
318. The bending moment diagram for a simply supported beam carrying a uniformly distributed load of ‘w’ per unit length, will be
(A) A horizontal line
(B) A vertical line
(C) An inclined line
(D) A parabolic curve
Answer: D
319. When one plate overlaps the other and the two plates are riveted together with two rows of rivets, the joint is known as
(A) Single riveted lap joint
(B) Double riveted lap joint
(C) Double riveted single cover butt joint
(D) Double riveted double cover butt joint
Answer: B
320. When a body is subjected to a direct tensile stress (σ) in one plane, the maximum shear stress is __________ the maximum normal stress.
(A) Equal to
(B) One-half
(C) Two-third
(D) Twice
Answer: B
321. The ductility of a material __________ with the increase in percentage reduction in area of a specimen under tensile test.
(A) Increases
(B) Decreases
(C) Remains same
(D) None of these
Answer: A
322. Rivets are generally specified by
(A) Thickness of plates to be joined
(B) Overall length
(C) Shank diameter
(D) Diameter of head
Answer: C
323. The simply supported beam ‘A’ of length ‘l’ carries a central point load ‘W’. Another beam ‘B’ is loaded with a uniformly distributed load such that the total load on the beam is ‘W’. The ratio of maximum deflections between beams ‘A’ and ‘B’ is
(A) 5/8
(B) 8/5
(C) 5/4
(D) 4/5
Answer: B
324. The rectangular beam ‘A’ has length ‘l’, width ‘b’ and depth ‘d’. Another beam ‘B’ has the same length and depth but width is double that of ‘A’. The elastic strength of beam ‘B’ will be _________ as compared to beam ‘A’.
(A) Same
(B) Double
(C) Four times
(D) Six times
Answer: B
325. The bending moment in the center of a simply supported beam carrying a uniformly distributed load of w per unit length is
(A) Zero
(B) wl²/2
(C) wl²/4
(D) wl²/8
Answer: D
326. The polar modulus for a solid shaft of diameter (D) is
(A) πD²/4
(B) πD³/16
(C) πD³/32
(D) πD⁴/64
Answer: B
327. The slenderness ratio is the ratio of
(A) Area of column to least radius of gyration
(B) Length of column to least radius of gyration
(C) Least radius of gyration to area of column
(D) Least radius of gyration to length of column
Answer: B
328. A simply supported beam ‘A’ of length ‘l’, breadth ‘b’ and depth ‘d’ carries a central load ‘W’. Another beam ‘B’ of the same dimensions carries a central load equal to 2W. The deflection of beam ‘B’ will be __________ as that of beam ‘A’.
(A) One-fourth
(B) One-half
(C) Double
(D) Four times
Answer: C
329. When a bar of length ‘l’ and diameter ‘d’ is rigidly fixed at the upper end and hanging freely, then the total elongation produced in the bar due to its own weight is (where w = Weight per unit volume of the bar)
(A) wl/2E
(B) wl²/2E
(C) wl³/2E
(D) wl⁴/2E
Answer: B
330. In a riveted joint, when the rivets in the various rows are opposite to each other, the joint is said to be
(A) Chain riveted
(B) Zig-zag riveted
(C) Diamond riveted
(D) None of these
Answer: A
331. When a rectangular bar of length l, breadth b and thickness t is subjected to an axial pull of P, then linear strain (ε) is given by (where E = Modulus of elasticity)
(A) ε = P/b.t.E
(B) ε = b.t.E/P
(C) ε = b.t/P.E
(D) ε = P.E/b.t
Answer: A
332. Which of the following statement is correct?
(A) The size of hole drilled in riveting plates is less than the actual size of rivet.
(B) The center to center distance between two consecutive rivets in a row is called margin.
(C) Rivets are generally specified by its shank diameter.
(D) Tearing of plates can be avoided by taking the pitch of rivets equal to 1.5 times the diameter of rivet hole.
Answer: C
333. A beam of triangular section is placed with its base horizontal. The maximum shear stress occurs at
(A) Apex of the triangle
(B) Mid of the height
(C) Center of gravity of the triangle
(D) Base of the triangle
Answer: B
334. The Young’s modulus of a material is 125 GPa and Poisson’s ratio is 0.25. The modulus of rigidity of me material is
(A) 30 GPa
(B) 50 GPa
(C) 80 GPa
(D) 100 GPa
Answer: B
335. In the above question, the normal stress on an oblique section will be maximum, when θ is equal to
(A) 0°
(B) 30°
(C) 45°
(D) 90°
Answer: A
336. In a simply supported beam carrying a uniformly distributed load w per unit length, the point of contraflexure
(A) Lies in the center of the beam
(B) Lies at the ends of the beam
(C) Depends upon the length of beam
(D) Does not exist
Answer: D
337. In case of eccentrically loaded struts __________ is preferred.
(A) Solid section
(B) Hollow section
(C) Composite section
(D) Reinforced section
Answer: C
338. In a thin cylindrical shell subjected to an internal pressure p, the ratio of longitudinal stress to the hoop stress is
(A) 1/2
(B) 3/4
(C) 1
(D) 1.5
Answer: A
339. The unit of modulus of elasticity is same as those of
(A) Stress, strain and pressure
(B) Stress, force and modulus of rigidity
(C) Strain, force and pressure
(D) Stress, pressure and modulus of rigidity
Answer: D
340. The stress at which the extension of the material takes place more quickly as compared to the increase in load, is called
(A) Elastic limit
(B) Yield point
(C) Ultimate point
(D) Breaking point
Answer: B
341. Two bars of different materials and same size are subjected to the same tensile force. If the bars have unit elongation in the ratio of 2:5, then the ratio of modulus of elasticity of the two materials will be
(A) 2 : 5
(B) 5 : 2
(C) 4 : 3
(D) 3 : 4
Answer: B
342. In a thick cylindrical shell subjected to an internal pressure (p), the maximum radial stress at the inner surface of the shell is
(A) Zero
(B) p (tensile)
(C) -p (compressive)
(D) 2p (tensile)
343. When a body is subjected to direct tensile stresses (σx and σy) in two mutually perpendicular directions, accompanied by a simple shear stress τxy, then in Mohr’s circle method, the circle radius is taken as
(A) [(σx – σy)/2] + τ
(B) [(σx + σy)/2] + τ
(C) (1/2) × √[(σx – σy)² + 4τ²xy]
(D) (1/2) × √[(σx + σy)² + 4τ²xy]
Answer: C
344. A section of beam is said to be in pure bending, if it is subjected to
(A) Constant bending moment and constant shear force
(B) Constant shear force and zero bending moment
(C) Constant bending moment and zero shear force
(D) None of the above
Answer: C
345. Modular ratio of the two materials is the ratio of
(A) Linear stress to linear strain
(B) Shear stress to shear strain
(C) Their modulus of elasticities
(D) Their modulus of rigidities
Answer: C
346. The relation between modulus of elasticity (E) and modulus of rigidity (C) is given by
(A) C = m.E/2 (m + 1)
(B) C = 2(m + 1)/m.E
(C) C = 2m.E/(m + 1)
(D) C = (m + 1)/2m.E
Answer: A
347. The Rankine’s constant for a mild steel column with both ends hinged is
(A) 1/750
(B) 1/1600
(C) 1/7500
(D) 1/9000
Answer: C
348. In a watch, the spring is used to store strain energy. This energy is released
(A) To stop the watch
(B) To run the watch
(C) To change the time
(D) All of these
Answer: B
349. When a column is subjected to an eccentric load, the stress induced in the column will be
(A) Direct stress only
(B) Bending stress only
(C) Shear stress only
(D) Direct and bending stress both
Answer: D
350. Two shafts ‘A’ and ‘B’ are made of same material. The shaft ‘A’ is solid and has diameter D. The shaft ‘B’ is hollow with outer diameter D and inner diameter D/2. The strength of hollow shaft in torsion is _________ as that of solid shaft.
(A) 1/16
(B) 1/8
(C) 1/4
(D) 15/16
Answer: D
351. A thick cylindrical shell having r₀ and ri as outer and inner radii, is subjected to an internal pressure (p). The maximum tangential stress at the inner surface of the shell is
(A) [p (r₀² + ri²)] / (r₀² – ri²)
(B) [p (r₀² – ri²)] / (r₀² + ri²)
(C) 2pri²/ (r₀² – ri²)
(D) (r₀² – ri²) / 2pri²
Answer: A
352. A beam of uniform strength has
(A) Same cross-section throughout the beam
(B) Same bending stress at every section
(C) Same bending moment at every section
(D) Same shear stress at every section
Answer: B
353. When a circular bar tapering uniformly from diameter d₁, at one end to diameter d₂ at the other end, is subjected to an increase in temperature (t), then the thermal stress induced is (where α = Coefficient of linear expansion, and E = Modulus of elasticity for the bar material)
(A) α.t.E.d₁/d₂
(B) α.t.d₁/E.d₂
(C) α.t.d₂/d₁.E
(D) d₁.t/ α.E.d₂
Answer: A
354. A shaft of diameter D is subjected to a twisting moment (T) and a bending moment (M). If the maximum bending stress is equal to maximum shear stress developed, then M is equal to
(A) T/2
(B) T
(C) 2T
(D) 4T
Answer: A
355. The maximum deflection of a fixed beam of length ‘l’ carrying a total load ‘W’ uniformly distributed over the whole length is
(A) Wl3/48EI
(B) Wl3/96EI
(C) Wl3/192EI
(D) Wl3/384EI
Answer: D
356. Factor of safety is defined as the ratio of
(A) Ultimate stress to working stress
(B) Working stress to ultimate stress
(C) Breaking stress to ultimate stress
(D) Ultimate stress to breaking stress
Answer: A
357. A pressure vessel is said to be a thin shell when the ratio of wall thickness of the vessel to its diameter is __________ 1/10.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: B
358. The unit of stress in S.I. units is
(A) N/mm²
(B) kN/mm²
(C) N/m²
(D) Any one of these
Answer: D
359. . A rod is enclosed centrally in a tube and the assembly is tightened by rigid washers. If the assembly is subjected to a compressive load, then
(A) Rod is under compression
(B) Tube is under compression
(C) Both rod and tube are under compression
(D) Tube is under tension and rod is under compression
Answer: C
360. The load required to produce a unit deflection in a spring is called
(A) Flexural rigidity
(B) Torsional rigidity
(C) Spring stiffness
(D) Young’s modulus
Answer: C
361. The bending moment at a section tends to bend or deflect the beam and the internal stresses resist its bending. The resistance offered by the internal stresses, to the bending, is called
(A) Compressive stress
(B) Shear stress
(C) Bending stress
(D) Elastic modulus
Answer: C
362. A thin cylindrical shell of diameter (d), length (l) and thickness (t) is subjected to an internal pressure (p). The hoop stress in the shell is
(A) pd/t
(B) pd/2t
(C) pd/4t
(D) pd/6t
Answer: B
363. Fatigue test is carried out for
(A) Stresses varying between two limits of equal value, but of opposite sign
(B) Stresses varying between two limits of unequal value, but of opposite sign
(C) Stresses varying between two limits of unequal value but of same sign
(D) All of the above
Answer: D
364. The neutral axis of a beam is subjected to __________ stress.
(A) Zero
(B) Maximum tensile
(C) Minimum tensile
(D) Maximum compressive
Answer: A
365. Two beams, one of circular cross-section and the other of square cross-section, have equal areas of cross-sections. When these beams are subjected to bending,
(A) Both beams are equally economical
(B) Square beam is more economical
(C) Circular beam is more economical
(D) None of these
Answer: B
366. A body is subjected to two normal stresses 20 kN/m² (tensile) and 10 kN/m² (compressive) acting perpendicular to each other. The maximum shear stress is
(A) 5 kN/m²
(B) 10 kN/m²
(C) 15 kN/m²
(D) 20 kN/m²
Answer: C
367. The thermal or temperature stress is a function of
(A) Increase in temperature
(B) Modulus of elasticity
(C) Coefficient of linear expansion
(D) All of these
Answer: D
368. For long columns, the value of buckling load is __________ crushing load.
(A) Equal to
(B) Less than
(C) More than
(D) None of these
Answer: B
369. When a body is subjected to a direct tensile stress (σ) in one plane, then tangential or shear stress on an oblique section of the body inclined at an angle ‘θ’ to the normal of the section is
(A) σ sin 2θ
(B) σ cos 2θ
(C) σ/2 sin 2θ
(D) σ/2 cos 2θ
Answer: C
370. Whenever some external system of forces acts on a body, it undergoes some deformation. As the body undergoes some deformation, it sets up some resistance to the deformation. This resistance per unit area to deformation, is called
(A) Strain
(B) Stress
(C) Pressure
(D) Modulus of elasticity
Answer: B
371. According to Euler’s column theory, the crippling load for a column of length (l) with one end fixed and the other end hinged, is
(A) π²EI/l²
(B) π²EI/4l²
(C) 2π²EI/l²
(D) 4π²EI/l²
Answer: C
372. When there is a sudden increase or decrease in shear force diagram between any two points, it indicates that there is a
(A) Point load at the two points
(B) No loading between the two points
(C) Uniformly distributed load between the two points
(D) Uniformly varying load between the two points
Answer: A
373. According to Euler’s column theory, the crippling load for a column of length (l) fixed at both ends is __________ the crippling load for a similar column hinged at both ends.
(A) Equal to
(B) Two times
(C) Four times
(D) Eight times
Answer: C
374. A load which is spread over a beam in such a manner that it varies uniformly over the whole length of abeam is called uniformly ________ load.
(A) Distributed
(B) Varying
(C) Both A and B
(D) None of these
Answer: B
375. Which of the following statement is correct?
(A) A continuous beam has only two supports at the ends.
(B) A uniformly distributed load spreads uniformly over the whole length of a beam.
(C) The bending moment is maximum where shear force is maximum.
(D) The maximum bending moment of a simply supported beam of length l with a central point load W is Wl/8.
Answer: B
376. The shear force in the center of a simply supported beam carrying a uniformly distributed load of ‘w’ per unit length, is
(A) Zero
(B) wl²/2
(C) wl²/4
(D) wl²/8
Answer: A
377. Every direct stress is always accompanied by a strain in its own direction and an opposite kind of strain in every direction, at right angles to it. Such a strain is known as
(A) Linear strain
(B) Lateral strain
(C) Volumetric strain
(D) Shear strain
Answer: B
378. A beam extending beyond the supports is called
(A) Simply supported beam
(B) Fixed beam
(C) Overhanging beam
(D) Cantilever beam
Answer: C
379. The shear force and bending moment are zero at the free end of a cantilever beam, if it carries a
(A) Point load at the free end
(B) Point load at the middle of its length
(C) Uniformly distributed load over the whole length
(D) None of the above
Answer: C
380. Compression members always tend to buckle in the direction of the
(A) Axis of load
(B) Perpendicular to the axis of load
(C) Minimum cross section
(D) Least radius of gyration
Answer: D
381. In order to avoid tearing off the plate at an edge, the distance from the center of the rivet hole to the nearest edge of the plate (i.e. margin) should be (where d = Diameter of rivet hole in mm)
(A) d
(B) 1.5 d
(C) 2 d
(D) 2.5 d
Answer: B
382. A thin cylindrical shell of diameter (d) length (l) and thickness (t) is subjected to an internal pressure (p). The longitudinal stress in the shell is
(A) pd/t
(B) pd/2t
(C) pd/4t
(D) pd/6t
Answer: C
383. The maximum shear stress developed in a beam of rectangular section is __________ the average shear stress.
(A) Equal to
(B) 4/3 times
(C) 1.5 times
(D) Twice
Answer: C
384. The distance between the center of a rivet hole to the nearest edge of plate, is called
(A) Margin
(B) Pitch
(C) Back pitch
(D) Diagonal pitch
Answer: A
385. When a rectangular beam is loaded transversely, the maximum tensile stress is developed on the
(A) Top layer
(B) Bottom layer
(C) Neutral axis
(D) Every cross-section
Answer: A
386. The strain energy stored in a body, when suddenly loaded, is __________ the strain energy stored when same load is applied gradually.
(A) Equal to
(B) One-half
(C) Twice
(D) Four times
Answer: D
387. The load at which the column just buckles, is known as
(A) Buckling load
(B) Critical load
(C) Crippling load
(D) Any one of these
Answer: D
388. The steel bars in a reinforced cement concrete beam are embedded __________ of the beam.
(A) In the center
(B) Near the bottom
(C) Near the top
(D) At any position
Answer: B
389. A reinforced cement concrete beam is considered to be made of
(A) Homogeneous material
(B) Heterogeneous material
(C) Composite material
(D) Isotropic material
Answer: B
390. Principle plane is a plane on which the shear stress is
(A) Zero
(B) Minimum
(C) Maximum
(D) None of these
Answer: A
391. The polar moment of inertia of a hollow shaft of outer diameter (D) and inner diameter (d) is
(A) π/16 (D³ – d³)
(B) π/16 (D⁴ – d⁴)
(C) π/32 (D⁴ – d⁴)
(D) π/64 (D⁴ – d⁴)
Answer: C
392. The springs in brakes and clutches are used to
(A) To apply forces
(B) To measure forces
(C) To store strain energy
(D) To absorb shocks
Answer: A
393. A beam encastered at both the ends is called
(A) Simply supported beam
(B) Fixed beam
(C) Cantilever beam
(D) Continuous beam
Answer: B
394. A spring used to absorb shocks and vibrations is
(A) Conical spring
(B) Torsion spring
(C) Leaf spring
(D) Disc spring
Answer: C
395. The bending moment at the free end of a cantilever beam is
(A) Zero
(B) Minimum
(C) Maximum
(D) None of these
Answer: A
396. The hoop stress in a thin cylindrical shell is
(A) Longitudinal stress
(B) Compressive stress
(C) Radial stress
(D) Circumferential tensile stress
Answer: D
397. In a stress-strain diagram as shown in the below figure, the curve ‘A’ represents
(A) Mild steel
(B) Soft brass
(C) Low carbon steel
(D) Cold rolled steel
Answer: B
398. The ratio of bulk modulus to Young’s modulus for a Poisson’s ratio of 0.25 will be
(A) 1/3
(B) 2/3
(C) 1
(D) 3/2
Answer: B
399. The ratio of shear modulus to the modulus of elasticity for a Poisson’s ratio of 0.4 will be
(A) 5/7
(B) 7/5
(C) 5/14
(D) 14/5
Answer: C
400. A column of length (l) with both ends fixed may be considered as equivalent to a column of length __________ with one end fixed and the other end free.
(A) l/8
(B) l/4
(C) l/2
(D) l
Answer: B
401. The pull required to shear off a rivet, in double shear, per pitch length is
(A) π/4 × d² × σt
(B) π/4 × d² × τ
(C) π/2 × d² × σt
(D) π/2 × d² × τ
Answer: D
402. The bending stress in abeam is __________ bending moment.
(A) Equal to
(B) Less than
(C) More than
(D) Directly proportional to
Answer: D
403. When a change in length takes place, the strain is known as
(A) Linear strain
(B) Lateral strain
(C) Volumetric strain
(D) Shear strain
Answer: A
404. The volumetric strain is the ratio of the
(A) Original thickness to the change in thickness
(B) Change in thickness to the original thickness
(C) Original volume to the change in volume
(D) Change in volume to the original volume
Answer: D
405. A welded joint as compared to a riveted joint has __________ strength.
(A) Same
(B) Less
(C) More
(D) None of these
Answer: C
406. In a beam subjected to pure bending, the intensity of stress in any fibre is _________ the distance of the fibre from the neutral axis.
(A) Equal to
(B) Less than
(C) More than
(D) Directly proportional to
Answer: D
407. The relation between Young’s modulus (E) and bulk modulus (K) is given by
(A) k = (3m – 2)/m.E
(B) k = m.E/(3m – 2)
(C) k = 3(m – 2)/m.E
(D) k = m.E/3(m – 2)
Answer: D
408. The shear force of a cantilever beam of length l carrying a uniformly distributed load of w per unit length is __________ at the fixed end.
(A) Zero
(B) wl/4
(C) wl/2
(D) wl
Answer: D
409. The strength of the shaft is judged by the_____________.
(A) Torque transmitted by the shaft
(B) Length of the shaft
(C) Dia. of the shaft
(D) None of these
Answer: A
410. A simply supported beam ‘A’ of length l, breadth b, and depth d carries a central point load W. Another beam ‘B’ has the same length and depth but its breadth is doubled. The deflection of beam ‘B’ will be __________ as compared to beam ‘A’.
(A) One-fourth
(B) One-half
(C) Double
(D) Four times
Answer: B
411. In a simple bending theory, one of the assumptions is that the material of the beam is isotropic. This assumption means that the
(A) Normal stress remains constant in all directions
(B) Normal stress varies linearly in the material
(C) Elastic constants are same in all the directions
(D) Elastic constants varies linearly in the material
Answer: C
412. The maximum deflection of a fixed beam carrying a central point load lies at
(A) Fixed ends
(B) Center of beam
(C) l/3 from fixed ends
(D) None of these
Answer: B
413. The shear stress at the center of a circular shaft under torsion is
(A) Zero
(B) Minimum
(C) Maximum
(D) Infinity
Answer: A
414. A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The maximum normal stress will be
(A) -100 MPa
(B) 250 MPa
(C) 300 MPa
(D) 400 MPa
Answer: D
415. When a closely-coiled helical spring is subjected to an axial load, it is said to be under
(A) Bending
(B) Shear
(C) Torsion
(D) Crushing
Answer: C
416. In a beam where shear force changes sign, the bending moment will be
(A) Zero
(B) Minimum
(C) Maximum
(D) Infinity
Answer: C
417. The strength of the unriveted or solid plate per pitch length is
(A) d.t.σc
(B) p.t.σt
(C) (p – d) t.σt
(D) π/2 × d² × τ
Answer: B
418. The tensile test is carried on __________ materials.
(A) Ductile
(B) Brittle
(C) Malleable
(D) Plastic
Answer: A
419. The bending moment diagram for a simply supported beam loaded in its center is
(A) A right angled triangle
(B) An isosceles triangle
(C) An equilateral triangle
(D) A rectangle
Answer: B
420. A bar of length ‘L’ meters extends by ‘l’ mm under a tensile force of ‘P’. The strain produced in the bar is
(A) l/L
(B) 0.1 l/L
(C) 0.01 l/L
(D) 0.001 l/L
Answer: D
421. A closely coiled helical spring is of mean diameter (D) and spring wire diameter (d). The spring index is the ratio of
(A) 1/d
(B) 1/D
(C) D/d
(D) d/D
Answer: C
422. The compression test is carried on __________ materials.
(A) Ductile
(B) Brittle
(C) Malleable
(D) Plastic
Answer: B
423. If the tearing efficiency of a riveted joint is 50%, then ratio of rivet hole diameter to the pitch of rivets is
(A) 0.20
(B) 0.30
(C) 0.50
(D) 0.60
Answer: C
424. The breaking stress is __________ the ultimate stress.
(A) Equal to
(B) Less than
(C) Greater than
(D) None of these
Answer: B
425. The section modulus (Z) of a beam is given by
(A) I/y
(B) I.y
(C) y/I
(D) M/I
Answer: A
426. The Rankine’s formula holds good for
(A) Short columns
(B) Long columns
(C) Both short and long columns
(D) Weak columns
Answer: C
427. When two main plates are kept in alignment butting each other and riveted with cover plate on both sides of the main plates with two rows of rivets in each main plate, the joint is known as ________ double cover butt joint.
(A) Single riveted
(B) Double riveted
(C) Multi riveted
(D) None of these
Answer: B
428. When a shaft is subjected to a twisting moment, every cross-section of the shaft will be under
(A) Tensile stress
(B) Compressive stress
(C) Shear stress
(D) Bending stress
Answer: C
429. The maximum bending moment of a simply supported beam of span l and carrying a point load W at the center of beam, is
(A) Wl/4
(B) Wl/2
(C) Wl
(D) Wl²/4
Answer: A
430. A tensile test is performed on a mild steel round bar. Its diameter after fracture will
(A) Remain same
(B) Increase
(C) Decrease
(D) Depend upon rate of loading
Answer: C
431. Transverse fillet welds are designed for
(A) Tensile strength
(B) Compressive strength
(C) Shear strength
(D) Bending strength
Answer: A
432. The product of the tangential force acting on the shaft and its distance from the axis of the shaft (i.e. radius of shaft) is known as
(A) Bending moment
(B) Twisting moment
(C) Torsional rigidity
(D) Flexural rigidity
Answer: B
433. The unit of strain is
(A) N-mm
(B) N/mm
(C) mm
(D) No unit
Answer: D
434. In spring balances, the spring is used
(A) To apply forces
(B) To measure forces
(C) To absorb shocks
(D) To store strain energy
Answer: B
435. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum shear stress will be
(A) 400 MPa
(B) 500 MPa
(C) 900 MPa
(D) 1400 MPa
Answer: B
STRENGTH of Materials objective questions with answers pdf download online exam test
So far we have been discussing the positive aspect of the comparative cost theory which showed that the theory has a scientific purpose of determining the direction of trade.
The theory also has a welfare aspect, in which it serves as a proof for the advantages of free trade. Comparative cost difference between the nations not only directs them to trade freely with each other, but also ensures them gainful effects from such trade.
The question arises: does this conclusion hold well if the trading nations exhibit different stages of economic development? The classical economists are very optimistic in their reply.
They are of the view that uninterrupted trade between a rich and a poor country on the basis of comparative cost difference will not only make the former better off, but also function as an engine of growth in the latter.
International trade, by widening the markets and by stimulating the division of labour, accelerates the process of economic development in the underdeveloped countries.
But, the protectionists and growth economists have cast their doubts regarding the growth aspects of free trade in the less developed countries and have, therefore, recommended an alternative engine of growth, (i.e. domestic industrialization) for these economies.
They considered the classical theory of comparative cost inapplicable to the conditions and growth problems of these countries.
